Preparing for possible invasion by the Jem'Hadar, the soldiers of the Dominion, Kira determines that Deep Space Nine lacks the firepower to defend itself - until Sisko arrives in an experimental vessel called the Defiant, a warship originally designed to fight the Borg. His plan is to travel with his officers into the Gamma Quadrant and locate the "Founders," the unseen leaders of the Dominion, with the purpose of demonstrating the Federation's peaceful intent. If this is impossible, the presence of the Defiant with all of its weaponry will show Sisko's determination to defend against an invasion. Along for the mission is T'Rul, a Romulan with a cloaking device, which will render the Defiant invisible from the Jem'Hadar during the search. Guarding the device is Lt. Commander Eddington of Starfleet Security, who has been ordered to assume Odo's duties. Realizing he is being relieved, an angry Odo resigns.Review
Meanwhile, Sisko coerces Quark into joining the mission because of his past dealings with the Karemma, a race that lives under Dominion rule. Odo also comes aboard the Defiant at the request of the Bajoran government, but shows to be more edgy than normal. After entering the Gamma Quadrant, T'Rul engages the cloaking device, allowing the Defiant to barely escape detection from two Jem'Hadar ships.
Ornithar, a Karemma official, is brought aboard the Defiant and reveals to Quark and Sisko that a race called the Vorta has ordered all communications for the Dominion directed to a relay station on Callinon VII. Odo's curiosity draws him strangely toward starcharts of the sector, specifically those of the Omarion Nebula. Quark then disembarks while the Defiant heads for the Callinon system. Once there, Dax and O'Brien transport to the unmanned facility. But just as Dax notices that most of the outgoing transmissions are being sent to specific coordinates, her communications to Sisko are cut off. With Jem'Hadar ships on the way, he reluctantly leaves the two behind and orders a course set for the coordinates.
Kira confronts Odo in his quarters to discuss his odd behavior. He confides to her about feeling a mysterious compulsion to travel to the Omarion Nebula - and is convinced that he must go there immediately. Kira tries to make sense of this, but they are interrupted when the Defiant is attacked by three Jem'Hadar vessels.
The Defiant is pummeled by the onslaught, and is boarded by Jem'Hadar soldiers, who overwhelm the bridge crew. Kira and Odo defend themselves, but Kira is shot and falls unconscious. She awakens aboard a shuttlecraft with Odo, who has left the Defiant dead in space. His course - for the Omarion Nebula ...
Odo and Kira have landed on a lone planet in the Omarion Nebula, which they have discovered is Odo's homeworld. A Female Shapeshifter encourages him to begin the slow process of learning who he is, and discovering the bond they share, known as the "great link." Odo is pleased to be reunited with his people, but they don't like Kira because she is a "solid" lifeform. Meanwhile, forced to abandon the Defiant during the Jem'Hadar attack days before, Sisko and Bashir are traveling alone in a shuttle when O'Brien and Dax, who have met the Founders, rescue them. Upon returning to the space station, Sisko learns that the Federation is negotiating a peace treaty with the Dominion, represented by one of the Founders, Borath.Review
When Sisko finds out that the Romulans have been excluded from the peace talks, he expresses his concern to Admiral Nechayev, but she dismisses his fears. On the other side of the wormhole, Kira is unable to contact Sisko because of interference from a hidden power source, while Odo struggles with his "lessons" at shapeshifting. Later, the Female Shapeshifter tells Odo that they came to this secret planet a long time ago, as a result of persecution at the hands of the Solids, then reveals he was sent as an infant to explore the galaxy, then return home.
While looking for Odo, Kira discovers a locked door - something for which shapeshifters would have no use. This arouses her curiosity. Back on the space station, a fight erupts between O'Brien and a Jem'Hadar soldier because the newcomers have been given free reign. Sisko then discovers that the Federation has signed the treaty, agreeing to give control of the Bajoran sector - including the station and the wormhole - to the Dominion. Over Sisko's objections, he and his crew will be reassigned.
A happy Odo tells Kira he has decided to remain with his people, but Kira asks him to help her get to the hidden power source before she departs. He is intrigued when Kira reveals it is behind the locked door she has found. Meanwhile, Jem'Hadar soldiers shoot Romulan officer T'Rul in cold blood, then attack an outraged Sisko. Deciding that matters have gotten out-of-hand, Sisko then bands with Garak, Dax, Bashir, and O'Brien on a suicide mission to steal a Runabout, collapse the wormhole, and keep the Dominion on its side of the galaxy forever.
Garak is killed while Sisko and the others escape. Once aboard the Runabout, they fire on the wormhole, collapsing it in a blinding explosion. Meanwhile, Odo unlocks the mysterious door, where he and Kira find Jem'Hadar soldiers waiting. The two are taken to an interrogation room where Sisko and the Defiant crew sit with their eyes closed, devices attached to their heads. Borath is there, revealing that he is really a Vorta, experimenting on the crew to determine how much they will sacrifice to avoid war with the Dominion. The Female Shapeshifter then arrives, disclosing that her people are the mysterious Founders. Saddened that his own race is responsible for so much death and misery, Odo demands that his friends be released, then chooses to return with them. Surprised that their experiences since the Defiant attack didn't really happen, Sisko and the crew head back to the station. Knowing the truth about his people, Odo realizes now that, even though he may feel like an outsider, his place is with his friends.
With bar business especially slow, Rom complains to Quark that their only customer, a Klingon named Kozak, says he's out of money. Quark approaches Kozak, who responds by pulling a knife. But he is so inebriated that he trips and falls on the blade, killing himself. Quark is horrified, but when the bar is flooded with patrons flocking to see what happened, he recognizes a good business opportunity and takes credit for killing Kozak in self-defense. Thrilled with his newfound popularity, he ignores Odo's warning that Kozak's family might retaliate. Sure enough, D'Ghor, Kozak's brother, soon arrives and collars Quark.Review
A fearful Quark prepares to tell D'Ghor the truth, but learns that his life would be spared only if Kozak died honorably in battle. Thus sanctioned, Quark continues to revel in his role as a "slayer of Klingons" until Grilka, Kozak's widow, arrives and realizes the Ferengi is lying. She takes Quark to the Klingon home world against his will, where she explains that a provision in Klingon law grants consideration to a female left without a male heir after the accidental death of a spouse. This might allow her to lead her own House. But since Kozak instead died "in battle," the lack of a male heir would cause the House of Kozak to fall, and D'Ghor, who has been enemies with his brother's family for years, could take over. Unwilling to let that happen, Grilka conducts a ceremony where Quark winds up married to the widow.
Grilka brings Quark before the Klingon High Council and presents Quark as her husband, reminding the Council that, as Kozak's killer, Quark may be invited to take his place, and his wife. Much to the chagrin of D'Ghor, Council leader Gowron promises to consider her words, allowing the House of Kozak to be known as the House of Quark until he reaches a decision.
Grilka is not certain what to do next, until Quark volunteers to go over the financial records of the House. He discovers that D'Ghor has been systematically attacking Kozak's family's assets for years, weakening the House in order to prime it for a takeover. Together, Quark and Grilka present their findings to the High Council. But instead of conceding defeat, D'Ghor demands vengeance through personal combat, revealing that Quark lied about Kozak's death by bringing in Rom as a surprise witness.
With his life now on the line, Quark decides to run rather than face D'Ghor in battle. This means Grilka must return to Gowron without a husband, and with little chance of stopping D'Ghor from taking everything she has. Surprisingly, however, Quark arrives at the Council meeting armed to fight. As D'Ghor prepares to attack him, Quark suddenly tosses away his bat'leth sword, then reminds the Council that killing a defenseless Ferengi would be an execution instead of a honorable victory. An unmoved D'Ghor prepares to deliver the death blow anyway, but Gowron stops him, ashamed by his total lack of honor. Gowron then grants Grilka special dispensation to lead her House on her own. Quark is given a divorce, and he returns to Deep Space Nine a true hero in his brother Rom's eyes.
While experimenting with a keyboard, the musically untrained Dax inexplicably plays a melody she seems to remember from somewhere, then suddenly develops a short temper toward her fellow crew members. She soon wanders onto the Promenade, where everyone mysteriously vanishes. A robed, masked figure stands above her, then a longer version of the melody begins to play. Dax is gripped with fear as the figure appears again, blocks her path, then removes the mask, only to reveal another. She then backs into Quark, at which point the Promenade is bustling with life again - and the masked figure is gone.Review
Concerned about the hallucination, Dax has Bashir examine her. He discovers that her levels of isoboramine, a neurotransmitter that mediates synaptic functions between Jadzia and the Dax symbiont, are dangerously low. Aboard the Defiant, Sisko and Bashir go with Dax to the Trill homeworld, where the Symbiosis Commission's Dr. Renhol administers a drug to bring up Dax's isoboramine levels. But Dax later has another hallucination in which two men from the Commission, dressed in uniforms dated about a hundred years earlier, attempt to capture her.
Dax meets with Timor, one of the Guardians, who are unjoined Trill dedicated to caring for symbionts. He says Jadzia is really experiencing memories from one of Dax's previous hosts. Later, the Defiant's computer identifies the mysterious music as a piece composed over 80 years before by a Trill named Joran Belar. When Dax is shown a picture of him, she suddenly experiences another hallucination in which the masked figure kills a Trill doctor and is revealed to be Joran. Dax then has a seizure and goes into neural shock.
Dr. Renhol says that if Dax's isoboramine levels don't improve in forty-eight hours, the Dax symbiont will have to be removed and Jadzia's life sacrificed. Desperate to save their friend, Sisko and Bashir turn to Timor, but he becomes nervous and evasive, leading them to believe he is hiding something. They access Joran's file, and find it has been purged. Sisko and Bashir then contact Joran's brother, Yolad, who says his sibling was killed after murdering the doctor who felt Joran was not suitable for being joined with a symbiont. Then, Yolad confides that he believes his brother actually was joined, despite claims in the official records to the contrary. Sisko and Bashir realize then that the symbiont was probably Dax.
Sisko and Bashir confront Dr. Renhol just as she is preparing to remove the Dax symbiont from Jadzia, then reveal that they have discovered the cover-up. Dax was once mistakenly joined with Joran, and this knowledge was blocked from Dax's memory - but now the memory block is deteriorating. They also know that Joran's experience contradicts claims that only one out of a thousand people is suitable for joining. In reality, almost half the population can be joined, a fact that would cause chaos as everyone fought to possess the few prized symbionts. When Sisko and Bashir threaten to reveal this secret, Dr. Renhol allows them to try and save Jadzia. They return to Timor, who has Dax enter the pool of symbionts, where the memories of Joran are safely re-integrated with her other memories. She emerges ready to deal with this painful, secret past - a whole new lifetime of thoughts.
Kira is surprised when she sees records indicating that she was incarcerated at Elemspur, a Cardassian prison, 10 years ago. Certain she was never at the prison, Kira tracks down a man listed as her one surviving cellmate. The stranger claims to remember Kira, but she has no idea who he is and decides to learn the truth. Kira departs for Bajor, but is kidnapped, waking up on Cardassia, where an official named Entek tells her she has been brought home. Looking in a mirror, Kira is horrified to see that she now looks like a Cardassian.Review
Entek gently tells her she is Iliana Ghemor, a field operative of the Obsidian Order who volunteered for an undercover assignment on Bajor a decade ago. The Cardassians captured the real Kira, gave her memories and appearance to Iliana, then sent the replacement back to Bajor to infiltrate the resistance. Entek leaves, giving the disbelieving Kira a data rod containing a personal message Iliana recorded before she left. Soon afterward, Legate and Central Command member Tekeny Ghemor arrives, claiming he is her father and they are in his home. Kira dismisses him, and is surprised when he seems genuinely hurt that his daughter's suppressed memories haven't yet returned.
Back on Deep Space Nine, Garak reveals that Kira may be held by the Obsidian Order. Sisko decides to go to Cardassia and find her, forcing Garak to join him and Odo. On Cardassia, Ghemor tries desperately to jar Kira's memory of her life as his daughter, but she refuses to either believe him or trust his intentions. Entek attempts to interrogate Kira, saying they need information from Iliana's mission, but is frustrated that her memory is not resurfacing. Entek then shows her a younger Kira's dead body, which has been cryogenically preserved, looking just like it did in the prison record.
Kira believes the body to be a fake, but Entek then speaks of experiences she has never told another person. For the first time, Kira begins to doubt herself, but she doesn't give up and decides to escape, only to have Ghemor catch her. Later, Entek returns and begins to interrogate her yet again. An angry Ghemor comes in and dismisses Entek, invoking his status with the Central Command, then tells Kira that, even though it will break his heart, he will get her away from Cardassia.
As the final arrangements are made, Ghemor reveals that he is a dissident. This puts the pieces of the puzzle together for Kira. She realizes that Entek is not really after her, but is only using her resemblance to Ghemor's daughter to get him to betray the Central Command. Entek then enters with two Obsidian Order agents who surround Kira and Ghemor. But Sisko, Garak, and Odo appear and stop them, with Garak killing Entek in the process. Ghemor returns with Kira to Deep Space Nine, where tests prove she is Bajoran. Ghemor vows to find his real daughter, but also tells Kira that, until then, she is the closest thing to family he has.
A Boslic Captain talks Quark into purchasing the wreckage of a ship that crashed in the Gamma Quadrant. Unfortunately, he ends up with much more than he bargained for when he finds a newborn alien infant hidden inside. Quark brings the baby to the Infirmary, where the child's presence reminds Sisko of his teenaged son Jake's own infancy - and Sisko's fatherly concern now that Jake is dating Mardah, a 20-year-old Dabo girl. Bashir notices that the baby has a phenomenal metabolic rate, and the child develops so rapidly that he changes from an infant to what looks like an eight-year-old boy in a few hours.Review
While the boy is no more than two weeks old genetically, he is already able to speak. Bashir soon determines that his advanced skills are artificially implanted as the result of genetic engineering. The crew quickly sees what kind of alien he is when the boy matures again - into a violent, teenaged Jem'Hadar.
Sisko plans to send the teenager to Starfleet Command for study, but Odo objects, knowing what it is like to live as a lab specimen. Despite the danger the Jem'Hadar poses, Odo wants to prove that he isn't just a programmed killing machine. He asks Sisko to let the boy stay, thinking he can control the alien since Jem'Hadar soldiers are bred to serve Odo's race of shapeshifters. Because the child's race is dangerous to the Federation, Sisko is reluctant, but he lets Odo work with the boy. Later, Mardah joins Sisko and a nervous Jake for dinner. But, despite his initial thoughts, Sisko finds Mardah to be very nice - and learns some things about Jake in the process. Meanwhile, Odo talks to the alien, who shows his obedience, then expresses a desire to stay in Odo's quarters, which he allows.
Odo talks at length with the teenager, and learns that he wants to know more about the Jem'Hadar. But the boy's only desire seems to be for violence. Kira warns him that the child may be a lost cause - if he was engineered to kill, Odo will not be able to change him. Odo tries to show the teenager that there is more to life than fighting, but a holosuite battle reveals that the bloodlust remains. Later, Sisko has word that Starfleet has sent a ship to pick up the young Jem'Hadar. But before Odo can leave to tell the boy, he suddenly appears in the room, pulls a phaser on Sisko, and announces that he refuses to go where they plan to send him.
The teenager demands a Runabout so he and Odo can go home to the Gamma Quadrant, then takes him through the corridors en route for the vessel. Much to Odo's disappointment, the boy reveals that he wants to be a Jem'Hadar. But when Sisko attempts to stop him from leaving, Odo intercedes, insisting on returning the teenager to his homeland. Knowing that the Jem'Hadar will either kill someone or be killed rather than go with Starfleet, Sisko agrees. Odo handles this final task and returns to the station, sadder but wiser for his experience.
While working in the station's ore processing unit, O'Brien and Jake accidentally activate an automated Cardassian security program, which traps the pair and Sisko in the room. Throughout the station, monitors display an old message from Gul Dukat warning of a Bajoran "worker revolt" in the unit. Dax tries to beam out the three, but the computer requests an access code, which the Cardassians never revealed when they abandoned the station years ago. Jake crawls through a pipe and opens the hatch to the ore chute, allowing Sisko and O'Brien to get out just as lethal neurocine gas is released. Dukat's image reappears, announcing that the "workers" have escaped, after which the doors to Ops all slam shut.Review
Sisko, O'Brien, and Jake are now trapped in an ore processing bay. A force field keeps Dax, Bashir, and Kira stuck in Ops, while another one holds Odo and Quark in the Security Office. Dax inadvertently activates the security program's second level, a program designed to release neurocine gas through most of the station in five minutes. Garak suddenly arrives at Ops, using his Cardassian access code - which only works for him - to enter through the force field. At his suggestion, Kira destroys the life support system, which stops the gas and gives them twelve hours to regain control before the oxygen is depleted. Unfortunately, Kira's phaser blast has activated the third phase of the program. Dukat's recorded message now declares that the station is programmed to self-destruct in two hours.
Garak tries to make the computer think he is Dukat, but ends up initiating level four of the program - a series of phaser blasts which forces everyone to take cover. Then, to everyone's surprise, Gul Dukat transports into Ops to taunt the officers. But he can't leave the station when he tries, then a recorded message from his old superior, Legate Kell, appears. Dukat won't be allowed to flee his post during the "revolt," states the message - and his code won't stop the self-destruct.
They determine that the only option would be to reach a control junction and disengage the laser fusion initiator, but can't do anything while trapped in Ops. Meanwhile, Sisko, O'Brien, and Jake blast open the bay doors by detonating the unstable ore left inside, but are stopped from going far by more force fields. Back in Ops, Dax suggests creating a power surge to short out the force fields all over the station. The plan works, and Kira informs Sisko they have ten minutes before self-destruction. Sisko, O'Brien, and Jake have the only chance of reaching the control junction. Realizing they may not have time to disable the fusion initiator, Sisko decides instead to direct the explosion into the deflector shields. He crawls through a burning conduit, makes the adjustments, and as the destruct command is initiated, the shields absorb the blast and the station is saved.
While exploring the Gamma Quadrant in the Defiant, Sisko, Dax, Bashir, and O'Brien are shocked when a planet appears where none existed before. They are contacted by a woman named Seltin, who invites them to join her people on their world for a meal. During the feast, Seltin explains that the planet, Meridian, shifts between this dimension and another, where they exist as pure consciousness. When they return to this dimension, it is as if no time has passed for them even though decades have gone by in reality. Dax is intrigued by a Meridian named Deral, who explains to her that the periods when his planet exists in this dimension are getting shorter - this time, they will only be visible for 12 days, after which Meridian will shift back into its non-corporeal state for 60 years. Those intervals returning to Dax's dimension will soon be cut to a matter of minutes, after which the planet will become too unstable and simply cease to exist.Review
Sisko volunteers to help find a way to stabilize Meridian's dimensional shifts. Dax notices a possible anomaly in the sun's fusion cycle, and a probe is sent to investigate. While awaiting the readings, Dax and Deral take a long walk through Meridian's landscape, during which they give in to their growing attraction and kiss.
Dax soon discovers an imbalance in the sun's core is triggering the dimensional shifts. Unfortunately, while it is possible to equalize the time between shifts, it cannot be accomplished before the five days Meridian has left remaining in this dimension. Dax and Deral realize they will not see each other again until his planet returns in 60 years. Unwilling to lose her, Deral decides to leave Meridian and his people in order to go with Dax to the Alpha Quadrant.
Seltin is thrilled to hear that the next time Meridian returns to this dimension, it will remain for 30 years, allowing the group to have families and expand the settlement. But she is less than thrilled with Deral's announcement that he is leaving with Dax. He knows that the small society can't afford to lose a member, but remains determined to be with the woman he loves. Noticing Deral is torn, Dax presents an alternative - having her molecular structure altered in order to survive the dimensional shift. Realizing it's the only way they can be together, Dax decides to do this so she can remain on Meridian with Deral.
As the shift of Meridian begins, Dax's presence interferes with the process, making the planet unable to completely enter the other dimension. Trapped, Dax is left unable to breathe, but is then beamed aboard the Defiant. Sisko informs her that Meridian shifted successfully after her disappearance, letting Dax know that Deral is alive, but lost from her life for the next 60 years.
When Commander William Riker from the U.S.S. Enterprise visits the station, an intrigued Kira takes him on a tour, particularly of the Defiant. On the bridge of the docked ship, Kira uses her access code in order to show him more of the Deflant's operations. But as the ship springs to life, Riker suddenly stuns Kira with a phaser blast, then a man and a woman, Tamal and Kalita, transport aboard. Riker fakes an emergency on the warship and convinces Sisko to have it freed from the dock. The Defiant then engages warp drive and leaves the sector, at which point it is revealed that the man stealing the vessel is actually Thomas Riker, Will Riker's duplicate, created as the result of a freak transporter accident nine years ago.Review
Sisko and Odo inform Gul Dukat that Thomas Riker - who is believed to be a member of the Maquis, a terrorist group fighting against Cardassia - has stolen the Defiant. They fear that Dukat's superiors at Cardassian Central Command will assume Starfleet wanted the Maquis to have the warship. This would give the Cardassians an excuse to launch a full-scale invasion into the Demilitarized zone between their territory and Federation space in order to find the Defiant. Seeing no other option, Sisko agrees to join forces with Dukat to help destroy the vessel. Meanwhile, Riker makes a rendezvous with a group of Maquis ships, then gives the order to head for the Cardassian border.
Sisko accompanies Gul Dukat to the Cardassian homeworld's War Room, where they meet Korinas, an observer from the Obsidian Order. Sisko reveals that the Defiant has a cloaking device, but admits the ship may be detectable with an anti-proton beam. Meanwhile, Riker uses a decoy vessel to lure away Cardassian warships, then slips into their territory. Kira then sets off an explosion on board, which disables the cloaking device and causes the Defiant to lose power.
The Defiant is repaired, and Riker reveals to Kira that he believes renegade Cardassians have a secret base in the Orias system where they are building an invasion force. His mission is to destroy that operation. In the War Room, Sisko realizes that the Orias system is the Deflant's destination and suggests that a warship be sent there, but Korinas objects, informing them that the sector is controlled by the Obsidian Order - and any warship that enters will be destroyed.
The Defiant is located heading toward the Orias System and Dukat sends ten ships in pursuit. But he and Sisko are surprised when three more Cardassian warships suddenly appear in the sector, and they realize that the vessels belong to the Obsidian Order. On the Defiant, Riker engages in battle and finds himself at a considerable disadvantage. Then Sisko comes up with a plan. Since Dukat wants to know what the Obsidian Order is hiding, Sisko proposes that he allow the Defiant to safely return to Federation space in exchange for the information on the Orias system gathered in the Defiant's sensor logs after entering the area. Dukat accepts, provided the Cardassians also get Riker as a prisoner. Riker agrees and surrenders to Dukat's forces in order to save his friends on the Defiant, then prepares to spend the rest of his life in a Cardassian labor camp.
The Bajoran Gratitude Festival, an annual celebration, is about to get underway, and both Kira and O'Brien await the arrival of their loves. But while Kira's encounter with Bareil is sweet, O'Brien's long-anticipated reunion with his wife Keiko is strained - she is exhausted and their daughter, Molly, is sick. To make matters worse, Lwaxana Troi also arrives, and immediately seeks out Odo, hoping for a romantic rendezvous, but he is uninterested. Similarly, Kira is too busy setting up for the festival to spend time with Bareil, and Keiko is too tired to enjoy her time with her husband. But at the opening festivities, Lwaxana experiences a brief headache, which Bareil and Jake seem to feel simultaneously.Review
As the festival gets underway, Bareil and Kira finally find some time to spend together, but are interrupted by Jake, who insists on speaking with Kira in private. Once Bareil leaves, Jake shocks Kira by saying he is in love with her. Bareil, meanwhile, wanders to Dax, and finds himself suddenly smitten with her. As all this happens, Lwaxana continues her futile pursuit of Odo, then has another brief headache near Dax, who appears to feel it also. O'Brien's romantic endeavors are also thwarted as Keiko says her research on Bajor will keep her there for another few months, then storms away from her angry and hurt husband.
O'Brien talks with Quark, where the proprietor treats him to a taste of the Ferengi philosophy on women, inadvertently showing O'Brien how much Keiko means to him. Meanwhile, Kira finds Bareil, and is hurt when he dismisses her as no more than a friend. Dax, while hiding from Bareil, has joined Sisko, and surprises her friend with the announcement that she is really in love with him.
Bashir's examination of Dax reveals nothing wrong, and she pretends it was all a joke until she and Sisko are alone again, at which point she kisses him. Meanwhile, O'Brien speaks to Keiko through her locked bedroom door, telling her he will resign to stay together, but Keiko says she needs to think about it. Later, Odo, Lwaxana, and Bashir see Kira on their way to Sisko's upcoming party, and Lwaxana feels another headache, at which Bashir and Kira react. The two of them then go to the Infirmary, where they immediately kiss passionately.
At the party, Sisko watches in horror as Dax chases him, Bareil chases Dax, Bareil hits Sisko, Dax slugs Bareil, Jake moons over Kira, and Kira and Bashir can't keep their hands off each other. Keiko arrives at the party in a stunning red dress, walks up to her husband and tells him not to resign, then kisses him. Quark shows up, then proclaims his undying love for Keiko. Luckily, Sisko and Odo notice that before Quark saw Keiko, Lwaxana had a headache, after which Quark seemed to feel the same headache. Bashir discovers that Lwaxana has Zanthi Fever, in which Betazoids experiencing a headache from the condition project their amorous feelings for someone onto those in close proximity. To Sisko's surprise, it only affects people who already have a pre-existing latent attraction. Bashir cures her and says everyone will be back to normal in a few days. But for Keiko and O'Brien, the effects of this Gratitude Festival are real.
En route to a symposium in San Francisco, Sisko, Dax and Bashir are lost during transport to Earth from the Defiant. The trio materializes in San Francisco, but in the year 2024. Apprehended by a pair of policemen, Sisko and Bashir are taken to a "Sanctuary District" - a gated area of the city where homeless, mentally ill and unemployed people are locked away from the rest of society.Review
Separated from the others, Dax is found by a prominent businessman named Chris Brynner, who takes her to his office and helps her obtain the ID card necessary to exist in this society. Dax doesn't reveal where she comes from, but tells him that her friends are missing. Meanwhile, in the Sanctuary District, Sisko and Bashir are taken to a processing center, where no records of their existence are found. Sisko learns the date and realizes that they have arrived just days before a crucial event in history, the Bell Riots, which occurred in the area of the city where he and Bashir are now confined.
Sisko tells Bashir that residents in the District will take hostages, but a man named Gabriel Bell, after whom the riots were named, will sacrifice his life to save them. Hundreds of innocent people will be killed during the riots, but Sisko and Bashir can do nothing, or this pivotal moment in history, which led to sweeping social reforms, could be altered forever. Later, Sisko and Bashir are given ration cards to obtain meals and sent out to find a place to sleep among the abandoned buildings.
On the Defiant, Kira, Odo and O'Brien realize their comrades were transported back in time, but cannot pinpoint the exact date, and have only a limited number of search attempts they can make. In the Sanctuary District, Sisko and Bashir meet Webb, a homeless but proud man who asks them to try and help the community, but they must refuse his request in order to avoid any contact that could change history. Later, Sisko and Bashir end up in a scuffle over Bashir's food card, during which a bystander who steps in to help is killed. Sisko is shocked to discover the dead man is Gabriel Bell.
When Kira attempts to contact Earth to discuss the situation, she learns that everything connected with Starfleet has vanished. Odo, O'Brien and Kira realize their missing crewmates have altered history, and that the Defiant is all that remains of the Federation. Back in the past, Chris Brynner does some research and learns that Jadzia's friends are among the thousands of people behind the walls of the Sanctuary District. Meanwhile, Sisko and Bashir realize that they must step in to undo the damage to history resulting from Bell's death. They arrive at the processing center just as the residents take hostages. As the riots begin, Sisko joins the aggressors, identifying himself as Gabriel Bell.
Sisko, posing as Gabriel Bell of the 21st century, takes charge of the hostage situation in the Processing Center as rioting begins within the Sanctuary District, and tells the angry residents that this is their chance to voice their grievances. Bashir reminds him that Bell is destined to die at the end of this turning point in Earth history. On the outside, Dax realizes that Sisko and Bashir are in danger and prepares to locate them. Meanwhile, Kira and O'Brien attempt transporting into different time periods to find their friends, with no success. Back in the center, Sisko convinces Webb, a decent family man, to act as their representative, but Webb is cut off from the computer interface terminal when he tries to communicate their plight. Then, police Detective Preston contacts Webb and asks to meet him.Review
Sisko joins Webb for the meeting, where they demand that all Sanctuary Districts be closed and the Federal Employment Act reinstated, and Preston agrees to present their demands to the Governor. Preston is later met by Chris and Dax, who can't convince the official to help them locate Sisko and Bashir. Determined, Dax waits until they aren't looking and slips away.
Kira and O'Brien transport once more into the past, but again choose the wrong time period. Meanwhile, as the riots continue, Preston offers to reduce the charges against Sisko and Webb if they release the hostages, but the two refuse to back down from their demands. Later, Dax is brought to the center, her combadge taken after having been captured upon entering the Sanctuary District.
Dax plays along with Sisko and Bashir, then tells them she can convince Chris to restore the group's computer access. After recovering her missing combadge, Dax slips back into the outside world. Soon, scores of residents are telling their stories to millions of people over the computer interface. Unfortunately, the Governor is unmoved, and tells Detective Preston to send in her troops.
Kira and O'Brien transport to the correct time period and soon locate Dax. Meanwhile, Sisko and Webb herd the hostages into a safe area of the center, just before a SWAT team bursts in, killing Webb and most of the others. One of the officers accidentally shoots at a hostage, but Sisko jumps in front of the man and takes a bullet to the shoulder. As the SWAT team leaves the center and National Guard personnel take control of the Sanctuary District, Sisko and Bashir are allowed to leave, and their ID cards are switched with those of two dead men. The former hostages promise to tell what really happened, and Sisko and Bashir return to the future, having restored history to its normal course.
When a serious accident nearly destroys a Bajoran transport arriving at the space station, Kai Winn manages to escape basically unharmed, but Vedek Bareil is critically injured. As Bashir operates on him while Kira worries, Winn informs Sisko that they were en route to a secret meeting to initiate peace talks with the Cardassian Central Command, and reveals that Bareil is the driving force behind the discussions. Unfortunately, Bashir is unable to save Bareil. However, as the doctor prepares to perform an autopsy, he notices a faint indication of life. After hours of intense work on Bareil's brain, Bashir is able to revive the dead man.Review
Bashir says Bareil could be back on his feet in a few weeks. But Winn is anxious to resume talks right away, and since Bareil is also determined, Bashir agrees to let him advise Winn from his bed. However, Bareil's circulatory system begins to fail, and Bashir tells him that he must be placed in stasis for an undetermined period of time. Feeling the obligation to bring about peace between Bajor and Cardassia, Bareil insists that Bashir find another solution. The doctor suggests an experimental drug that will let Bareil function for a few days - at the possible expense of his life. Against Bashir's judgment, Bareil tells him to try it.
Winn begins negotiations at the station, and it quickly becomes apparent that she is not comfortable in the role. Winn states to Sisko that, without Bareil, any hope of peace will die. Toward that end, she continues to ask him for advice, despite his obvious agony. Bashir then tells Bareil that the drug has already done irreversible damage to his organs. While artificial replacements can be inserted, Bashir recommends that Bareil go into stasis to avoid further damage, but he implores Bashir to do whatever is necessary to keep him going through the negotiations. The doctor turns to Winn, asking her to release Bareil from any more responsibility. But Winn is afraid to stand alone and refuses. However, when she returns to Bareil for another round of advice, his brain begins to fail.
The damage to the left side of Bareil's brain is irreversible, and Bashir grimly reports that he will not regain consciousness on his own. At the insistence of Kira and Winn, Bashir uses artificial brain implants to revive Bareil once again. Kira is by Bareil's side when he recovers from the surgery, and is devastated to discover that his feelings and emotions are basically gone. However, he retains the capacity to help Winn through the final negotiations, and the peace treaty is signed. But the other half of Bareil's brain soon begins to fail. Kira begs Bashir to save him with another artificial implant, but the doctor gently refuses, unwilling to reduce Bareil to a machine. Kira sadly accepts his words and asks to be left alone with the man she loves for the final hours of his life.
While traveling in a Runabout, Kira and Odo learn that a Maquis ship has ambushed a Lissepian vessel. They pursue the attacking ship to a deserted moon, where it crashes. Kira and Odo land on the moon, which is virtually uninhabitable and rocked by seismic activity. They split up within a group of caverns where the fugitive may be hiding, but Kira soon summons Odo with a distress call. He hurries to her side to find a crystal formation growing around Kira's foot, trapping her.Review
The crystal, which Odo cannot break, rapidly grows to just above Kira's knee. Atmospheric interference makes it impossible for him to either free her with the Runabout's transporter or send a distress signal back to the station. Odo then returns to the caverns to hear the sound of phaser blasts. Kira says that she just exchanged shots with the Maquis fugitive, but both missed. This, however, is the least of her problems - both her legs are now entirely covered in crystal.
Tremors shake the cavern while the crystal continues to grow around Kira. Odo brings in equipment to build a makeshift ultrasonic generator in an attempt to shatter the crystal. It has now grown to cover Kira's rib cage, making it difficult for her to breathe. Odo realizes that finding the right frequency might take longer than the few hours left before Kira is covered completely, but he is determined not to leave her stranded, and they betray just a bit of emotion toward each other. Then, suddenly, the cavern is shaken by a powerful tremor.
Odo morphs into a dome to shield Kira and the generator from the falling debris. But after trying every possible frequency, the crystal remains intact and grows to reach the middle of Kira's chest. Realizing there is nothing more Odo can do, Kira orders him to leave and save himself.
Odo refuses to go, despite Kira's reminder that if he stays, he will die along with her. But Odo says he cannot leave - because he is in love with Kira. After a moment, Kira shocks Odo by replying that she is in love with him, too. The increasingly suspicious Odo remains virtually silent for an hour, while the crystal grows up to Kira's neck. But when Kira then admits she isn't really in love with him, Odo realizes that she would never risk their friendship by lying. He points a phaser at her and demands to know what happened to the real Kira. The woman and crystal then morphs into the female shapeshifter Odo met when he discovered his homeworld. Knowing Odo's feelings for Kira, she planned the entire scenario to trick Odo into believing Kira died, hoping this would prompt him to return home. Angry, Odo makes her reveal Kira's location, and he then rescues his friend. They then return to the station, with Odo's deepest feelings still a secret from Kira.
In the wake of the peace treaty with Cardassia, Sisko is excited about working with two Cardassian scientists who are assigned to help deploy a subspace relay in the Gamma Quadrant - a project which, if successful, will allow communication through the wormhole for the first time. But Vedek Yarka warns that an old Bajoran prophecy predicts destruction of the wormhole, as three "vipers" will return to their "nest" in the sky. He deduces that the scientists are the vipers and the station must be their nest. Still, there are only two Cardassians arriving, and Sisko believes the project is too important to abandon. Later, the Cardassian scientists, Ulani and Gilora, arrive, and immediately put the crew at ease with their friendly manner. However, when they announce that another scientist will soon be joining them, Kira is concerned, believing this is the third "viper" in the prophecy.Review
Yarka begs Kira to have Sisko send away the Cardassians, but she will not let her faith interfere with her duties. After Dejar, the third scientist, arrives at the station, Gilora and O'Brien prepare to receive the signal from the Gamma Quadrant, while Dejar and Ulani travel there with Sisko, Kira, and Dax on the Defiant in order to set up the relay. As soon as they arrive, the crew encounters a large rogue comet, which Kira sees as the "sword of stars" mentioned in the prophecy.
Kira tells Sisko she believes the prophecy is coming true, and that Sisko, as the Emissary of Bajoran lore, must make a decision just as it foretells. Sisko, however, has always been unwilling to accept that he actually is the Emissary. He then has Dax send the first transmission through the wormhole, but it fails. The modified signal instead triggers the wormhole to open violently and experience a brief, drastic increase in gravity, which alters the comet's course, causing it to head directly for the anomaly. If the comet enters it, the material in the core will make the wormhole collapse permanently - which is apparently part of the prophecy.
Back at the station, O'Brien and Gilora modify the Defiant's phasers in order to vaporize the entire comet at once. But when the ship returns to the Gamma Quadrant to implement the plan, the weapons relay malfunctions, causing the phasers to instead fire a standard burst, which splits the comet into three fragments - all of which remain on course for the wormhole.
Gilora reveals that Dejar, who is a member of the Obsidian Order, sabotaged the phasers. Once Dejar is detained, Sisko and Kira board a shuttlepod and maneuver it between the comet fragments, generating a subspace field around the pieces as they travel through the wormhole. The pair is successful, as the fragments safely enter the Alpha Quadrant with just a minimum of the deadly material leaking into the wormhole. Amazingly, the material also forms a subspace filament which allows transmissions to come from the Gamma Quadrant. Kira realizes that the prophecy has come true - the symbolism was just interpreted incorrectly. The "vipers" were actually the comet fragments, which permanently wedged open the "temple gates" of the wormhole. Sisko returns to the station with new respect for Bajoran prophecy, and for his own prophesized role in Bajor's fate.
Zek, the Ferengi Grand Nagus, pays a visit to Deep Space Nine and moves in to Quark's quarters, where he undertakes an important project. After displacing Quark from his home, the Nagus reveals that he has been rewriting the Rules of Acquisition. Overcome with excitement, Quark and his brother Rom rush to read the volume, thrilled to have a head start on what they think will be the path to unimaginable profit. But they are shocked to read the first rule: "If they want their money back ... give it to them."Review
Quark and Rom read through the New Rules of Acquisition, which have been revised to reflect qualities of kindness instead of profit and greed. Amazingly, Zek is advising his people to change their ways. Quark is mortified, especially after he later discovers that Zek has established a Ferengi Benevolent Association - and named Rom the senior administrator of the project.
Zek believes Rom can be molded into a new kind of Ferengi who operates "beyond greed." But Quark will have nothing of it - he is convinced something is wrong with the Nagus. He is unsure what to do next, until Zek tells him about the gift he plans to present to the Bajoran people. Quark and Rom later sneak into the Nagus's shuttle to see the gift for themselves, and are astonished to find one of the missing orbs of the Bajoran prophets.
Against Quark's warning, Rom opens the box containing the orb. Quark is exposed to the sacred object, which shows him a vision in which the Grand Nagus reveals the New Rules of Acquisition were a gift. After recovering from the experience, Quark realizes the Rules are not a gift to the Ferengi people, but a gift to Zek from the aliens within the wormhole. Checking Zek's logs, Quark learns that he did visit the wormhole for a brief period, during which he could have communicated with the aliens. Quark surmises that he was hoping to use their ability to see through time to make profit, but something must have gone wrong. He decides the only way to help Zek is to take him back to the wormhole.
Inside the wormhole, Quark encounters the aliens, who explain that they were so bothered by their encounter with the materialistic Zek that they restored him to an earlier, less adversarial state of existence. They threaten to do the same to Quark, but he instead offers a bargain - if they return Zek to his original state, they will never be bothered by another Ferengi. The aliens agree, Zek is back to normal, and the Ferengi way of life is saved.
A Romulan delegation arrives to study reports on the Dominion, a privilege granted in exchange for the use of a cloaking device aboard the Defiant. Meanwhile, O'Brien, at Quark's riding out a mild case of radiation poisoning from an accident, is suddenly transported to another part of the bar, where he sees himself having a conversation with Quark. He just as suddenly returns to where he was, then falls over in pain. Bashir blames the radiation and assures O'Brien that hallucinations are a normal side effect. But when O'Brien returns to the bar five hours later, he has the same conversation with Quark that he "hallucinated." Dax theorizes that O'Brien's exposure to radiation could have caused him to temporarily shift five hours forward in time. Then, O'Brien experiences another timeshift - into the middle of a brawl in Quark's between the Romulans and some Klingons.Review
Bashir examines O'Brien in the present and determines that the timeshifts pose a serious threat to his life. Five hours later, O'Brien returns to Quark's to wait for the brawl, and the Klingons soon arrive and exchange blows with the Romulans. O'Brien timeshifts again, and this time sees himself in a corridor. He watches as his future self opens a wall panel and is killed by a blast from a hidden phaser.
After shifting back, O'Brien leads Sisko and Odo to the wall panel, but they find nothing. They assume that a weapon will soon be placed within it over the next five hours. While Bashir works to rid O'Brien's body of the residual radiation, Kira reports that she has moved the Romulans to the quarters adjacent to the wall panel. When Odo discovers that someone has put a surveillance device behind the panel, he suspects the Klingons are spying on the Romulans. O'Brien then shifts five hours into the future again - and sees his dead body in the Infirmary.
In the future, Bashir reveals to O'Brien how the radiation killed him. When O'Brien shifts back, the doctor is able to use this knowledge to save him. Meanwhile, Dax locates the cause of the shifts, which is a quantum singularity orbiting the space station. It periodically affects the radiation in O'Brien's body and triggers the timeshifts. O'Brien then shifts again into the future and finds himself aboard a crowded Runabout in the midst of an emergency evacuation - during which he watches as the station explodes and the wormhole collapses.
Hoping to learn how both the station and the wormhole are destroyed, O'Brien uses a device to flood himself with radiation in order to travel to the future again. Once there, he and his future self join forces, discovering that the quantum singularity is inside a cloaked Romulan Warbird, which becomes visible and attacks the station. While the timeshifting O'Brien becomes dangerously sick from the radiation, his future self is forced to take the device and return to the other's time period, where he tells Sisko what will happen. The commander deduces that the Romulans plan to eliminate the threat posed by the Dominion, making the station's destruction look like an accident from the wormhole collapse. Sisko expels the Romulans, and the future O'Brien must get used to living a few hours in his past.
An alien named Altovar approaches Bashir to obtain a restricted substance. The doctor refuses, prompting Altovar to later break into the Infirmary. Bashir arrives and tries to stop him, but the alien renders him unconscious with an electrical discharge. When Bashir recovers, he finds the temples of his hair graying, and the station dark and deserted. Just the most vital systems still function, and although he periodically hears strange whispering sounds, the only inhabitants found are Garak and a terrified Quark. Bashir and Garak split up in hopes of learning the fate of the others. Suddenly, his path is blocked by a forcefield, and he senses a presence coming toward him.Review
Thinking quickly, Bashir ducks inside a turbolift and narrowly escapes the pursuing Altovar. He exits to find Kira, O'Brien, Odo, and Dax engaged in a heated discussion. Bashir now appears to have aged 25 years, but the group is too busy debating each other to notice. The doctor realizes that the whispering, the crew's strange behavior, and the technical problems must be connected. O'Brien fixes the communications relay, and the group hears the same whispers. As the sounds become clearer, they prove to be the distant voices of the crew, stating that Bashir is in a telepathically-induced coma and will be dead in less than three hours. The doctor scans himself and discovers that he is indeed in a coma.
Bashir realizes that the rest of the group really isn't there - this scenario is actually happening in his mind, which is represented by the station, and the others just embody different aspects of his personality - fixing the station will bring Bashir out of his coma. Unfortunately, Dax is captured by the alien, and Bashir suddenly finds himself with Garak, who directs the doctor to Ops in order to repair the damage. On his way, Bashir sees Sisko, who represents the best aspects of the doctor's personality. But Altovar captures Sisko, then tells Bashir he will kill each part of his personality before finally letting him die.
While trying to get to Ops, Bashir, who appears about 75 now, finds Kira dead and Odo dying. He and O'Brien end up at Quark's, where the crowd is betting on how and when Bashir will die. Altovar appears, killing Quark, and Bashir starts to run away, but is terrified to discover he has broken his hip.
Bashir, now about 100 years old, is helped to Ops by Garak, who keeps encouraging him to give up. Bashir then realizes that Garak is actually Altovar. At this point the alien reveals his true form, but Bashir, having recovered some of his confidence, gains the upper hand. He returns to the Infirmary, realizing that this is the center of his world - and, therefore, the place from which he should repair the damage. Immediately, he is able to restore the lights, trap Altovar in a forcefield, and disintegrate the alien. He then quickly regains consciousness, surrounded by his crewmates, who he prepares to tell of his bizarre experience.
Sisko is abducted by a double of O'Brien, who takes him to the mirror universe that Kira and Bashir visited a year ago. This O'Brien explains that Sisko's counterpart, the leader of the Terran rebellion against the Klingon/Cardassian Alliance, has been killed. O'Brien wants Sisko to pose as his dead double and convince a Terran scientist with the Alliance to join the rebels. That scientist is Jennifer Sisko, the counterpart of Sisko's late wife. Since she is building a device that will betray the secret location of the rebels, Sisko must convince her to join them before she completes her work or the rebels will have to kill her. Unwilling to watch Jennifer die again, Sisko agrees to intervene. He meets the rebel counterparts of Bashir, Rom, Tuvok from the starship Voyager, and also Dax, who is Sisko's mistress in this universe. Only O'Brien knows that Sisko is an impostor.Review
Terok Nor, the mirror Deep Space Nine, is ruled by Kira for the Alliance. She tells Jennifer that the bloodshed against the Terrans will end once her device is completed. But later, Kira tortures Terran slaves in the ore processing center with the help of Garak, her chief aide. Then, Kira discovers that Sisko is still alive.
With communicators hidden under their skin, Sisko and O'Brien take a rebel ship to Terok Nor. They are immediately captured and taken to Kira, who sends O'Brien to ore processing with the slaves and takes Sisko to her quarters. Later, Sisko meets Jennifer, who despises him, and without revealing his true identity, apologizes for his past treatment of her, then says that he has come to rescue her.
Sisko tries to convince Jennifer that the Alliance is her real enemy, and plans to kill the rebels once they are found. Sensing he may be winning her confidence, Sisko signals O'Brien. In ore processing, O'Brien receives the signal and causes a malfunction that allows him and the Terrans to escape. Meanwhile, Jennifer agrees to leave with Sisko, they meet O'Brien, then head for a waiting ship.
Before they can escape, however, they are cornered by Kira and her troops. While Kira waits for Sisko to surrender, he slips away and herds his entire group into the ore processing center, where they seal themselves within. When Kira, Garak, and her soldiers finally force their way in, Sisko calmly tells her that he has activated the station's self-destruct sequence, which only he can stop. Kira reluctantly agrees to let Sisko, Jennifer, O'Brien, and the Terrans go free in order to halt the imminent destruction. Sisko and the others return to the rebel encampment, where Jennifer admits to realizing that he's not really her husband. She kisses him goodbye, and Sisko returns to his universe just a bit sadder.
A peaceful afternoon is shattered when Garak's shop is destroyed by an explosion. Although the blast initially appears to be accidental, further investigation reveals that the explosion was, in fact, rigged to look like an accident. Sisko and Odo ask Garak who might want him dead, but the Cardassian is, as always, secretive. However, Odo learns that the blast was triggered by a sensor favored by Flaxian assassins, and realizes a Flaxian named Retaya arrived that morning.Review
Questioning Retaya reveals nothing, and Odo allows him to leave, then cancels Garak's security escort, hoping this will coerce Garak into sharing what he may know about the assassination attempt. Later, when Odo boards a Runabout to follow Retaya, Garak awaits him. Odo reluctantly agrees to let him go along as he follows the suspect. Unfortunately, they learn little about Retaya's motives - his ship explodes just as he goes into warp.
An analysis reveals that the Romulans were behind the explosion. Odo surmises that they hired Retaya to kill Garak - but why? Odo learns from an informant that the Romulans may be planning to invade Cardassia. He is also told that five former Obsidian Order operatives "coincidentally" died the day Garak's shop exploded. Odo shows Garak the list of dead men, then confronts him with the deduction that Garak blew up his own shop just to get Odo involved. Garak finally admits that he and the deceased were all associates of Enabran Tain, the past leader of the Obsidian Order. Realizing Tain might also be in danger, Garak attempts to contact him, and upon learning his former boss left mysteriously the day before, sets off with Odo to find him.
Garak instructs Odo to head for a planet near the Cardassian border where Tain has a safe house. Before they arrive, however, they are intercepted by a Romulan Warbird and captured. Inside the ship, they are brought before Tain, who shocks them with the news that he ordered the attempt on Garak's life.
Tain tells the pair that the Romulan Tal Shiar and the Obsidian Order have joined forces, preparing to take a fleet of Romulan and Cardassian warships into the Gamma Quadrant. Their mission is to destroy the Dominion by eliminating the Founders, after which Tain plans to resume his post as head of the Order. Hence, the reason why he ordered the deaths of Garak and anyone else with information that could be used against him. However, now that Garak is on board, Tain offers his protege a chance to work with him again. Despite Odo's warnings not to trust Tain, Garak says yes, leaving Odo to face the Romulans and an uncertain fate.
After rejoining his former Cardassian mentor, Enabran Tain, Garak helps him in a joint mission with the Obsidian Order and the Romulan Tal Shiar. Tain has masterminded a plan to destroy the Founders - Odo's people, who rule the Dominion - and their homeworld. Tain, along with Colonel Lovok of the Tal Shiar, leads a fleet of cloaked Romulan and Cardassian ships into the Gamma Quadrant, commanding them from their Romulan Warbird. Garak is told to question Odo, who is being held prisoner aboard Tain's ship. However, Odo says he knows none of his people's secrets. On the station, Sisko learns of Tain's mission, and is warned by Starfleet's Admiral Toddman to prepare for retaliatory attacks by the Jem'Hadar.Review
Fearing Odo is aboard one of the Romulan ships, Sisko and his officers, including Security Chief Eddington, defy a direct order from Toddman and take the Defiant into the Gamma Quadrant to search for Odo. Soon afterward, the ship suddenly and inexplicably decloaks, leaving them vulnerable to attack by the Jem'Hadar, the Dominion's soldiers. Meanwhile, as Tain, Garak, and Lovok head for the Founders' planet, Tain urges Garak to interrogate Odo and learn if his people have a secret defense system. Garak agrees, but finds himself conflicted.
On the Defiant, Eddington confesses to sabotaging the cloaking device, under orders from Toddman to prevent pursuit of Tain's fleet. Back at the Romulan ship, Garak interrogates Odo using a device that prevents him from changing his shape. Odo insists he is not hiding anything, but Garak persists, and Odo begins to literally dry up and fall apart. Unable to watch Odo's excruciating agony, Garak begs him to talk, and Odo reveals his secret - he wants to rejoin his people. Shaken, Garak deactivates the device and lets Odo finally morph into liquid form.
Garak claims that Odo knows nothing, and Tain orders Odo killed. However, Lovok and Garak convince him to spare Odo for later Romulan study. The fleet then reaches the Founders' planet and opens fire, destroying part of the surface, but there is no change in the life form readings. Garak discovers their ships have been lured into a trap - the planet is actually deserted. As he explains, their vessels are suddenly surrounded by 150 Jem'Hadar ships.
The Jem'Hadar attack, and Garak takes advantage of the chaos to escape and rescue Odo. Surprisingly, Lovok helps them get to their Runabout and reveals he is actually one of the Founders. His people learned of Tain's plan and encouraged it in order to bait the Obsidian Order and Tal Shiar into annihilation. Lovok tries to convince Odo to return home, but he refuses. Forced to leave behind Tain, Odo and Garak escape on their ship, and the Defiant rescues them from the Jem'Hadar assault. The Romulan/Cardassian fleet is destroyed as the crew returns to the Alpha Quadrant, barely escaping with their lives.
Sisko returns from a trip to Bajor with the blueprint for an ancient space vessel that operates like a sailboat, using solar pressure for propulsion. According to legend, the Bajorans used these ships to explore their star system 800 years ago, even going as far as Cardassia. Sisko decides to build one himself to see if this was possible, and painstakingly recreates the vessel, determined to prove the design was spaceworthy. He hopes to have Jake join him on the adventure.Review
After initially declining his father's invitation, Jake reconsiders, and the two prepare to depart the station. Before they do, Gul Dukat warns Sisko against putting so much stock in a Bajoran "fairy tale" of ancient contact. Sisko feels Dukat is only interested in disproving the notion that the Bajorans, not the Cardassians, were the first people between the two races to develop interstellar travel.
The trip gets off to a smooth start, and both Sisko and Jake enjoy their time together. Jake seizes the moment to tell his father that he has been offered a writing fellowship in New Zealand, and Sisko is thrilled, yet distressed because those studies will take his son away from Deep Space Nine. But before they can discuss it, one of the ship's sails gives way, forcing them to struggle for control.
Sisko jettisons the sail, concerned about continuing. Jake reminds his father that the ancient Bajorans probably ran into similar problems and didn't give up. Convinced, Sisko decides to proceed on course. Jake then reveals that he plans to delay taking the fellowship for a year because of his concerns that Sisko hasn't had someone special in his life since his wife's death. Then, without warning, their ship is caught in an eddy of light that inexplicably takes it to warp speed.
After the ship is thrown free of the invisible current, Sisko discovers he has no idea where they are, and fears the eddy, composed of faster-than-light tachyons, has carried their vessel light years away. Suddenly, Gul Dukat informs the two that they have entered Cardassian space. As Sisko and Jake realize they just proved the same thing could have happened 800 years ago, Dukat reluctantly congratulates them on recreating the journey of ancient Bajoran explorers who did successfully reach Cardassia then, and welcomes the two with a stellar fireworks display.
In Quark's, an agent named Brunt from the Ferengi Commerce Authority (FCA) - their version of the IRS - serves Quark with a Writ of Accountability for improper supervision of a family member. Quark and Rom's mother, Ishka, is charged with earning a profit - an illegal activity for Ferengi women. As the family's eldest male, Quark is held responsible. He and Rom return to their homeworld, Ferenginar, where Quark must convince Ishka to confess, as required by Ferengi law.Review
The brothers arrive at their childhood home with Brunt, but Quark is not comfortable with seeing his mother again. They are surprised to find Ishka wearing clothes, which is also illegal for Ferengi women. Brunt tells Quark he has three days to get his mother to sign a confession, then leaves. Later, Ishka confirms over dinner that she broke Ferengi law by investing a portion of her monthly stipend from Quark, earning a meager three bars of latinum in the process. Still, she refuses to confess, which angers her oldest son.
In her room, Ishka reveals to Rom that she will not admit to being wrong - this is a matter of pride, and proof that she is just as capable of earning profit as a man. But Quark discovers that Ishka has actually been conducting business transactions under dozens of aliases all over the Ferengi Alliance, making much more than just three bars of latinum. Even if Quark sells everything he owns, he will be unable to pay back what his mother has earned. Quite simply, he's ruined.
Quark confronts Ishka, who accuses him of being jealous of her financial acumen - just like his deceased father. With that, an infuriated Quark decides to turn in Ishka to the FCA. Rom tries to stop him, but the conversation deteriorates into a brawl, after which Ishka declares that if Quark insists on reporting her secret transactions, then she won't stand in his way.
In the Tower of Commerce, Quark waits outside Brunt's office when Rom suddenly rushes in with the news that Ishka will split her profits with Quark, fifty-fifty. Seeing the entire affair in a different light, Quark hurries home to accept Ishka's offer. But when he arrives, Quark learns Rom made up the story, lying to both of them to force a conversation between the two. Alone with Quark Ishka tells him that, since he is her son, she will sign the confession and give back the money. Later, she pays her reparations to Brunt, and a relieved Quark says his good-byes and leaves. Now alone with Rom, Ishka reveals that she outsmarted Quark and the Ferengi government yet again - by giving up only a third of her profits.
When the First Minister of the Bajoran Provisional Government dies, Kai Winn is appointed to his duties and about to be formally elected. Later, Winn approaches Kira with a special request. A group of farmers in Kira's home province refuse to return some soil reclamators that Winn needs for Bajor's recovery efforts in Rakantha Province. Their leader, Shakaar, also led Kira's resistance cell during the occupation, so Winn wants Kira to convince him to return the property. Kira is reluctant to go up against a friend, but agrees to do it for the good of Bajor.Review
Kira returns home and finds Shakaar, who calmly tells his side of the story: he only received the reclamators two months before, after a three-year wait, and was told that he and fellow farmers Furel and Lupaza would have their use for a year. But when Winn took over, they were ordered to return them immediately. Since the Rakantha project is geared toward farming products for export, while Shakaar's farmers are trying to feed their people, he sees his project as far more important. Kira encourages him to meet with Winn, hoping they can compromise.
Kira tells Winn that she has arranged a meeting, to which she agrees. Later, as Kira briefs Shakaar for the discussion, two security officers arrive to arrest him. Infuriated that Winn lied, Kira helps subdue the officers and escapes with Shakaar.
Now fugitives, Shakaar, Kira, and their comrades hide in the mountains where they once eluded the Cardassians. Weeks later, as Bajoran troops close in, Shakaar's exhausted group realizes there is no option but to stop running and fight. Reluctantly, he and Kira lead them into a canyon to set up an ambush.
Hiding in the canyon, Shakaar and Kira watch as the Bajoran troops enter their trap. But as they see the faces of their "enemies," the realization hits that they will be shooting former comrades-in-arms. Unwilling to do this, Kira and Shakaar drop their weapons and, after a brief conversation with the leader, Lenaris, a cease-fire is called. Later, Lenaris takes Kira and Shakaar to Winn's office, where Shakaar informs her that he has decided to enter the election for First Minister. Realizing a competitive election with the popular Shakaar will expose how Winn's actions brought Bajor to the brink of civil war, Winn decides to step down from the race.
Jadzia Dax prepares for her zhian'tara, the Trill Rite of Closure. During the ritual, Jadzia will meet Dax's previous hosts, which will be accomplished by transferring the memories of each into someone's body. Sisko, Kira, Bashir, Odo, Quark, O'Brien, and Leeta agree to participate, and a Guardian performs the ceremony. Kira undergoes the transference first, becoming Lela, Dax's initial host.Review
The Guardian leaves Jadzia alone with Lela, who exhibits several traits Dax has inherited. So do subsequent hosts O'Brien/Tobin and Leeta/Emony. Quark experiences some discomfort hosting a female entity, Audrid, while Bashir/Torias regrets that an accident ended his life too soon. Jadzia then prepares for her most difficult meeting - with Joran, who once committed murder. Sisko has volunteered to host his memories, and the transference is conducted inside a holding cell.
Sisko/Joran berates Jadzia, telling her she is not worthy of the Dax symbiont, then tricks her into lowering the forcefield and attempts to choke her. But Jadzia overpowers him with a few Klingon-style blows, bringing Sisko back. Later, she admits to Sisko that she may have put off her zhian'tara because she is afraid of not measuring up to the other hosts. Jadzia is still haunted by the time Curzon forced her out of the Initiate program. Did he feel she just wasn't good enough?
Odo has volunteered to host Curzon, and when the transfer occurs, he literally morphs into a combination of himself and the old man. Odo/Curzon is thrilled to see Sisko. When Jadzia joins them in Quark's, Sisko leaves, knowing she needs to speak with Odo/Curzon about her feelings of insecurity. But he says nothing to make her feel better, only that he felt sorry for her. Jadzia replies that when Curzon's memories are restored to her, she fears that without his respect, she won't respect herself. Odo/Curzon happily answers that she won't have that problem - Curzon and Odo love being joined, and have agreed that Curzon should stay in Odo's body permanently.
With Jadzia in danger of losing a part of herself, Sisko offers to talk to Odo/Curzon. Instead, she works up the courage to face him herself and demands that her memories be returned. Odo/Curzon initially refuses. But Jadzia stands up for herself, and uncovers the surprising fact that Curzon forced her out of the program because he was in love with her. She tells Curzon that she loves him too, and that they can be joined forever through Dax if he returns to her body. This convinces Odo and Curzon to separate, and Curzon's memories return to Jadzia, finally giving her the self-confidence she needs.
During a party celebrating Sisko's promotion to Captain, Admiral Krajensky takes him aside and quietly reveals that there has been a coup on the Tzenkethi homeworld that could threaten Federation colonists. Sisko and his crew are to take the Defiant and Krajensky to this sector. Soon after departing, they receive a distress signal from a colonist indicating that Barisa Prime is under attack from the Tzenkethi. The signal then goes dead - the colony has apparently been destroyed.Review
The crew sets course for Barisa Prime, but when Sisko tries to notify Starfleet Command, power fluctuations in the ship's communications circuitry prevent it. O'Brien and Dax go to work on the problem, and discover strange alien devices attached to almost every critical system throughout the ship. They determine that there is a saboteur aboard. Dax scans each member of the crew, and when she gets to Krajensky, he suddenly morphs into a Changeling and escapes.
The Changeling takes control of the Defiant, activating the cloaking device and arming the ship's weaponry. Sisko realizes that the visit from Krajensky, the coup, and the transmission from Barisa Prime were all faked - the Dominion is hoping to start a war between the Federation and the Tzenkethi. With the Defiant primed for battle and within seven hours of the Tzenkethi border, this looks likely if the Changeling is not located and stopped. Later, Dax is found unconscious in the engine room, forcing O'Brien to try to regain control of the ship without her. Realizing the gravity of the situation, Sisko decides that if this cannot be accomplished before they cross the border, he will be forced to destroy the Defiant.
Since the Changeling can take the form of any crew member, the officers are paired off for the search. Later, Sisko, Odo, Kira, a Bolian officer, and Eddington are separated from their partners, and each is suspicious that another is the Changeling. Odo remarks that the bleeding Sisko cannot be, because his blood would have reverted to a gelatinous state when leaving the body. Bashir draws blood from everyone, and when Eddington's seems to morph into orange goo, he is taken into custody. However, another Bashir is found, revealing that the duplicate is the Changeling. He escapes again as the ship enters Tzenkethi space.
With twelve minutes left before the ship's attack program will activate, Sisko initiates the auto-destruct sequence. O'Brien begins a last-ditch effort to access the sabotaged systems when two Odos appear. The Changeling then assumes his true form and attacks. During their fight, he takes a fatal fall into the warp core. But before dying, he whispers something to Odo. Regaining control of the Defiant, Sisko cancels the auto-destruct program. But the crisis isn't over. Odo later reveals to Sisko the Changeling's last words: "You're too late. We're everywhere."