The U.S.S. Enterprise is on a routine mission in deep space when a beautiful young woman beams onto the bridge. Without a word, she touches a band on her wrist and everyone is rendered unconscious. She moves around the bridge until finally she comes to Spock. Smiling, she lays a hand on the Vulcan's head, as if she's found what she was looking for.Review
When Kirk awakes, Spock is gone from the bridge. Before the captain can find out where his first officer has gone, McCoy calls, demanding his presence in sickbay immediately. Spock's body lays on a diagnostic table, on full life support. McCoy explains that his brain is gone ... miraculously removed with some technology that the doctor has never seen before. Every nerve was sealed and there was no blood lost. However, McCoy tells him if the Vulcan's brain isn't returned to his body within 24 hours, Spock will die.
Kirk orders the starship in pursuit of the woman's ship. By following their ion trail, the Enterprise arrives at the sixth planet in the Sigma Draconis system. When Kirk and party beam down, they find a rough, frozen world inhabited by two peoples: the Morgs, who are comprised solely of men, who live on the surface in a primitive culture, and the Eymorgs, an all female group who live deep under the planet's surface. While the Eymorgs live in a highly technological society, they don't understand that technology and are trained to perform various tasks - like the operation enabling them to steal Spock's brain - by what is known as the "Great Teacher." This "teacher" was left behind by ancient technologists who once lived on the planet.
McCoy, having fashioned a device which will control Spock's body without the aid of his brain, beams down with the Vulcan to join Kirk and his party. They find Kara, the woman who beamed aboard the Enterprise. They quickly realize that Kara doesn't have the skill or knowledge to have performed the operation on Spock, and she tells them about the Great Teacher.
Finally, Kirk finds Spock's brain. The Eymorgs have hooked it up to run their central control system. The brain is now revered as the "Controller," which they hope will control their central systems for the next 10,000 years. After trying unsuccessfully to get Kara to repeat the operation on Spock in reverse, McCoy submits to the Great Teacher device and gains the knowledge needed to restore Spock's brain and save the Vulcan's life.
Without their Controller, the Eymorgs fear for their existence. Kirk suggests they share their greater knowledge with the Morgs and live together on the surface.
Seeming tense and erratic, Captain Kirk takes the U.S.S. Enterprise into Romulan space and the ship is immediately surrounded by Romulan warships. Kirk and Spock beam aboard the Romulan flag-ship and confront the Romulan Commander, a woman. Kirk explains that his ship entered Romulan territory because of equipment malfunction. Spock, however, denounces this explanation, saying Kirk ordered them here, due to his reduced mental stability. This, not surprisingly, enrages the Captain. The Romulan Commander orders the U.S.S. Enterprise be taken to the Romulan base. Scotty, placed in command of the starship, refuses. McCoy is beamed aboard the flag-ship to tend Kirk, who has become irrational to the point of violence. When he arrives, Kirk attacks Spock who reacts, without thinking, by using the Vulcan death grip, killing Kirk.Review
McCoy returns to the U.S.S. Enterprise with Kirk's body, while Spock remains on the Romulan ship. Unknown to the Romulan Commander, this has all been a ploy to sneak the officers on board and steal the Romulan cloaking device. After Kirk's body has been removed to his ship, the Romulan Commander begins to try and entice Spock into defecting to the Romulan side.
Disguised as a Romulan, Kirk returns to the Romulan ship and steals the vessel's cloaking device and returns with it to the U.S.S. Enterprise. When the Commander discovers the theft, she feels betrayed and in retaliation decides to execute Spock. The Vulcan pretends to confess to her and ultimately stalls until Scotty is able to install the cloaking device on board the U.S.S. Enterprise. Spock is beamed back aboard the starship, but since the Romulan Commander was standing near him, she is also beamed aboard.
The Romulan Subcommander, now in charge of the flag-ship, gives chase, ordered by his commander to destroy the Federation ship. Fortunately, the newly-installed cloaking device works and the U.S.S. Enterprise makes good her escape, with the Romulan Commander on board a their prisoner.
Investigating a planet in danger of collision with an asteroid, Captain Kirk, Mr. Spock, and Dr. McCoy discover both Native American inhabitants and a strange alien obelisk. While examining the obelisk, Kirk is accidentally trapped inside. Trying to escape, he inadvertently triggers a device that gives him amnesia.Review
Unable to locate the Captain, Spock and McCoy return to the U.S.S. Enterprise to try and stop the asteroid from hitting the planet.
Now free from the obelisk, Kirk is found by the natives, who come to believe Kirk (calling himself Kirok with his damaged memory) is a god. Kirk both becomes the tribe's medicine chief and marries the priestess Miramanee.
Meanwhile, the U.S.S. Enterprise fails in its attempt to destroy the asteroid. Spock is able, however, to translate the obelisk's carvings. He learns that an alien race known as the Preservers transplanted the Indians to this world, and provided an asteroid deflector inside the obelisk to protect them.
Returning to planetary orbit, Spock and McCoy beam down. They find the natives, frightened that Kirk does not know how to use the obelisk to protect them, stoning Kirk and Miramanee. Rescuing the pair and restoring Kirk's memory, Kirk and Spock enter the obelisk and activate the deflector. The planet is saved but Miramanee, pregnant with Kirk's child, dies from her injuries.
When the U.S.S. Enterprise finds that all the adults in the Starnes Expedition to Triacus have killed themselves, they beam to the planet's surface to investigate. The children, however, are alive and well and strangely oblivious to their parents' fates.Review
They are beamed aboard the U.S.S. Enterprise while Kirk searches for an answer to the strange occurrences. The children summon their "friendly angel" Gorgan, who tells them to take the U.S.S. Enterprise to a planet he can control. By garbling Kirk's words and deceiving Spock, the children are able to take control of the starship. Finally, seeing Kirk's anxiety at the loss of his ship, Spock realizes that something is wrong and helps the Captain regain control.
Kirk shows the children tricorder tapes of their parents ... and their graves, demonstrating to them that Gorgan is not a "friendly angel" but an evil force. The loss of his believers renders Gorgan impotent and he fades into oblivion.
In an attempt to adapt Medusan technology to Federation use, and vice versa, the U.S.S. Enterprise picks up Medusan ambassador Kollos, instrument specialist Laurence Marvick and telepath Dr. Miranda Jones. The Medusans have a great beauty of character, but their physical appearance causes shock to the point of insanity in humanoids.Review
When Dr. Jones turns down her co-worker, Lawrence Marvick's, proposal of marriage in favor of staying with Kollos, Marvick tries unsuccessfully to kill Kollos. Instead, he is driven insane by a glimpse of the Medusan. He takes over the U.S.S. Enterprise engines, which he helped design, and drives the ship out of the galaxy into an indeterminate region. The crew experiences acute sensory distortion and Marvick finally dies.
While the crew cannot pilot the starship back to the galaxy, it is possible that Kollos can, with Spock forming a mind meld. Kirk distracts Dr. Jones, who jealously objects to Spock contacting Kollos in this manner. Kirk discovers why Dr. Jones is able to gaze upon Kollos ... she's blind.
Using Spock's body, Kollos pilots the U.S.S. Enterprise back to its galaxy, but the Vulcan forgets to wear his protective visor when restoring Kollos to his box, and goes insane. Dr. Jones mind-links with Spock and draws the Vulcan's mind back to reality. She then makes a permanent mind link with Kollos and transfers with him to the Medusan vessel.
Kirk ignores an alien buoy that warns the U.S.S. Enterprise that it is trespassing into Melkotian space and continues forward when the Melkots transport Kirk, Spock, McCoy, Scotty, and Chekov to a recreation of Earth's wild west. Here their instruments will not function and they are forced to relive, in "a manner befitting their heritage for trespassing," the shoot-out in Tombstone, Arizona on October 26, 1881.Review
The U.S.S. Enterprise party is transported to the OK Corral, but as they will not fire on the "Earps," the gunfighters cannot hurt them. Chekov, in the role of Billy Claiborne, is killed and Spock realizes that these events are not really transpiring. Through a series of mind melds, Spock is able to reject the illusions of the hostiles enabling the crew to succeed without shooting at the others. The Melkots are impressed by the peaceful behavior of the U.S.S. Enterprise party and return them, including Chekov, who had been killed in an earlier altercation, to the U.S.S. Enterprise. The Melkots agree to establish contact with the Federation.
A U.S.S. Enterprise landing party beams to a human-colonized planet in answer to a distress call. A Klingon ship, apparently damaged, is detected and a group of Klingons accuse Kirk of having damaged their ship. Kang, their leader, claims the U.S.S. Enterprise as a prize and Kirk beams the Klingons on board, reluctantly. However, Spock is warned by Kirk and quickly takes the Klingons prisoner. Both ships seem to have received the same, false, distress call.Review
A malevolent entity has entered into the U.S.S. Enterprise computer and excites both sides to aggressive behavior. It forces the ship out of control, rushing toward the galactic rim, while isolating a number of Klingons and U.S.S. Enterprise crew, heightening their sense of paranoia and violence turning them against each other. Phasers become swords and the battle begins.
Spock finally realizes that the entity feeds off hatred and emotional excitation and has acted as a catalyst to provoke combat, keeping the numbers on both sides even. Kirk is able, in the end, to make a common-cause truce with the Klingons and they drive the creature out of the ship with their laughter.
At the same time McCoy discovers that he has a year to live, the U.S.S. Enterprise encounters the asteroid Yonada which is determined to be artificially propelled. Its center is occupied by humanoids, whose ancestors built the asteroid "vessel" in an effort to escape the destruction of their solar system. However, the controls have become defective and Yonada is heading for collision with a Federation planet.Review
The people are ruled by Natira, a priestess who takes her orders from the central computer. While Kirk and Spock search for the central controls that will redirect the ship, McCoy and Natira fall in love. Kirk and Spock return to the U.S.S. Enterprise but McCoy, wishing to spend what little time he has left with the woman he's come to love, stays behind, marries Natira and accepts the "Instrument of Obedience" which punishes wrong thinking.
Soon after the marriage, McCoy calls Kirk, telling him that he may have found the controls for the asteroid. However, he is struck down by the "Instrument of Obedience" before he can tell them where. Kirk and Spock beam back to Yonada, remove the sensor from McCoy, and locate the controls. They manage to put Yonada back on course. In deciphering the computer's library, Spock finds a cure for McCoy's disease, and the doctor returns to the U.S.S. Enterprise. Natira must stay on Yonada to guide her people and so bids McCoy good-bye.
The U.S.S. Enterprise arrives in an uncharted area of space to answer a distress call from the U.S.S. Defiant. The starship is visible on their viewscreen, but sensors on board the U.S.S. Enterprise say it's not there.Review
Kirk, Spock, McCoy and Chekov beam aboard and spread out to investigate. Everyone aboard is dead ... apparently killed in a bizarre mutiny, although there are no life readings aboard. McCoy, in the ship's sickbay, tells Kirk that he can find no clue as to why the crew died, but has taken readings to study. Then, as his hand passes through a body and exam table, McCoy realizes the U.S.S. Defiant is dissolving.
Quickly Kirk orders them beamed back to the U.S.S. Enterprise, but Scotty explains that due to the poor stability of the space around them, he can only beam three aboard. After the usual debate, Kirk stays behind while the others beam back. When Scotty tries to bring Kirk aboard, his image wavers, and disappears. Interphase, Spock calculates, will occur in a little over two hours. In the meantime, they must wait. If the captain is still alive, they should be able to retrieve him then.
Complications arise when Chekov goes berserk and attacks Spock on the bridge. Slowly, more members of the crew fall prey to the "illness," attacking their crewmates. McCoy and his staff work round the clock to find a cure. When the doctor suggests Spock "put some distance" between the U.S.S. Enterprise and the U.S.S. Defiant, Spock explains that any movement in the weakened space could disturb both ship's positions and jeopardize Kirk's rescue.
At a little over an hour before interphase, a Tholian ship appears, telling Spock that the U.S.S. Enterprise has violated Tholian space. The Vulcan explains that they were answering a distress call and are waiting until they can retrieve Kirk. The Tholians agree to wait until the appointed time before taking action.
Unfortunately, when the interphase occurs, Kirk is not where he should be. Spock suspects that the Tholian's entrance into the area of space disturbed the U.S.S. Defiant's position. A funeral service is held for Captain Kirk, following which McCoy insists they view the Captain's last orders. Spock reluctantly agrees and the two men go to their friend's quarters and listen to Kirk's touching advice.
Uhura is the first to see Kirk's image floating before her, and for a time, McCoy thinks she's contracted the disease. But when he and Spock see the Kirk on the bridge, they realize that he is, in fact, still alive.
The Tholians decide that Spock has, in fact, lied to them and opens fire. Making a decision, Spock orders the phasers fired at the ship. The Tholian ship is disabled, but soon another ship joins it and they begin 'building' a sort of web made of shining filaments. Spock analyses the web and announces that if they don't bring Kirk aboard and leave before the web is completed, they "won't see home again." At the last minute, Spock orders full power against the web and the U.S.S. Enterprise is thrown outside the Tholian's trap, several parsecs from their former position. The hope is that Kirk, caught in the U.S.S. Enterprise tractor beam when they changed position, was brought with them.
Tensely McCoy waits with a hypo of tri-ox for Kirk, whose air is running out as he's successfully beamed on board the U.S.S. Enterprise, alive and unharmed. In a humorous tag, McCoy and Spock convince Kirk that there had been no time to view his final orders and Kirk, somewhat disappointed that his wisdom had gone unheard, says that he hopes there isn't a similar circumstance where the two men will view the tape.
When the U.S.S. Enterprise receives a distress call from the planet Platonius, Kirk, Spock and McCoy beam down to the planet's surface. There they find the planet's leader, Parmen, with a badly infected leg. The Platonians, while powerful psycho kinetics, have no resistance against physical injury. As Parmen's wife tells them, a cut or break in the skin can literally cause death. The only resident of Platonius that doesn't have "the power" is Alexander, a dwarf, who is everyone's jester and slave.Review
When Parmen's wound has healed and the landing party prepares to leave, they find the U.S.S. Enterprise's controls are frozen. Parmen has decided that it would be beneficial for them to have a resident doctor and tries to convince McCoy to remain. When he refuses, Parmen and the others try to convince him by subjecting Kirk and Spock to several humiliating scenarios. Still the doctor refuses and the three officers are locked away to ponder their plight.
After questioning Alexander, McCoy determines that the Platonians probably got their mental powers from eating the local foods. Something about Alexander's metabolism has kept him from acquiring those powers as well. McCoy prepares concentrated doses of kironide, the substance in the local food, and injects it into Kirk and Spock. Alexander, given the chance, refuses an injection. He doesn't want the same powers that his masters have.
As they discuss their next move, the shimmering of a transporter beam appear in the room and Lieutenant Uhura and Nurse Chapel appear. Without a word, they are jerked out of the room, as if controlled with invisible strings, and disappear. Kirk comments grimly that the men were apparently not entertaining enough for the Platonians.
Later, Uhura and Christine join the other officers, dressed in sparkling gowns and lavish makeup. Christine's is even vaguely Vulcan with slanted eyebrows and partially covered ears. What follows is a series of "games" designed to humiliate the U.S.S. Enterprise crew members and entertain the Platonians. McCoy, seated in a place of honor beside Parmen, is expected to accept the leaders offer to stay and serve as their physician.
Kirk and Spock are forced to fight each other and Spock is made to sing "Maiden Wine" to the two women. Finally, Spock is paired on a loveseat with Christine, while Kirk shares one with Uhura. They are forced to make advances on the women. The play gets nasty then, as Kirk and Spock take up whips, which they snap at their respective partners. By now, however, the doses of kironide are beginning to take effect and both officers now resist the Platonians powers and throw down their weapons.
Kirk tells Parmen that they can recreate this power whenever they want and if the Federation finds that Parmen and his people have fallen back to their old ways, there will be trouble. With this, Kirk calls for the U.S.S. Enterprise to beam them aboard ... along with Alexander, who will be coming with them to start a new life.
The U.S.S. Enterprise responds to a distress call from the planet Scalos; the call shows several Scalosians asking for assistance. Arriving at Scalos, however, the crew find only an empty city, with no life forms registering on tricorder scans. Compton, a young, inexperienced crewman samples the local water and disappears.Review
Beaming back up to the ship, the crew investigates while the U.S.S. Enterprise experiences a series of strange malfunctions. When an alien device is found in engineering, the ship is put on full alert. Back on the Bridge, Kirk sips coffee and suddenly finds himself "accelerated" far beyond the rest of his crew. After acceleration, he is able to see and interact with the missing Scalosians, who are now on his ship.
Kirk meets Deela, the Queen of the Scalosians, who specifically chose Kirk to be her consort. Deela reveals the Scalosians' plan to cryogenically freeze the crew of the ship so that they will have a ready gene pool to integrate into their radiation-contaminated one. Kirk also finds his missing crewman, Compton, and sees the effects of rapid acceleration - any damage to cells causes an accelerated death.
Kirk manages to send a message to Spock and McCoy warning them, and delays the Scalosians long enough for Spock to join Kirk in his accelerated state. Spock brings a possible antidote with him, and after stopping the Scalosians, and returning them to their planet, Kirk takes it. The Captain returns to normal, and Spock uses the advantage of his acceleration to repair several of the ship's systems, before he too returns to normal speed.
The U.S.S. Enterprise goes to pick up research personnel on the second planet of the star Minara. While Kirk, Spock and McCoy are on the surface, a radiation storm endangers the starship and Scotty takes the Enterprise out of orbit, sure that the planet's atmosphere will protect the landing party from radiation.Review
The three officers find themselves in an underground chamber shared with a mute humanoid which McCoy names "Gem." Two other humanoids, different from Gem, appear to them. They tell the men they are Vians, and take Kirk as a test subject to torture. He is assured, however, that it isn't he who is being tested. Gem, who turns out to be a fully functional empath, heals Kirk's wounds. The Vians tell the captain he must choose one of his men to be the next text subject. Each man volunteers, but McCoy wins, managing to anesthetize both Spock and Kirk, and is taken away by the Vians.
When he is returned to them, McCoy is near death. Gem attempts to cure him, but is frightened by the severity of his injuries. The Vians explain to them that they are testing Gem to see if her people are worthy as a species to be saved from their doomed sun. They are testing Gem's capacity for compassion and self-sacrifice. Overcoming her fears, Gem heals McCoy and the Vians decide that her species is to be saved. The officers are returned unharmed to the U.S.S. Enterprise.
Two United Federation of Planets members, Elas and Troyius, suffered war for centuries. With Klingon Empire expansion approaching the planets' system, Tellun, the Federation sends the U.S.S. Enterprise to lend assistance in a peace negotiation. The peace treaty is to be completed by the bonding in marriage of the two planets' leaders, the Dohlman of Elas and the leader of Troyius. The starship provides transport for the Dohlman to Troyius, while also offering a time and place for the Dohlman to learn the duties and customs of Troyius.Review
Upon her arrival on the U.S.S. Enterprise, it is clear that the Dohlman, Elaan, is an arrogant and reluctant bride. Ambassador Petri from Troyius attempts to educate Elaan in preparation of her wedding, but is rewarded with a knife wound. Captain Kirk must step in as Elaan's tutor to insure that the alliance takes place. Kirk takes a strong hand in Elaan's education, but his efforts are compromised when she begins to cry and he touches one of her tears. The Elasian tears of a Dohlman carry an infectious agent which acts as a powerful aphrodisiac.
While the captain fights the effects of Elaan's tears, a Klingon battlecruiser appears. In the ensuing melee, it is apparent that the Klingon captain is attempting to lure the starship into warp speed which, as Scotty soon discovers, would destroy the ship. A saboteur from the Elasian party has damaged the dilithium crystal chamber, rendering the crystal inert, and the ship nearly powerless.
While under attack, Spock detects strong energy readings which emanate from a crystal necklace of Elaan's - made of dilithium. Fitting the raw crystals into the anti-matter chamber, the ship is able to fend off the Klingons and continue to Troyius. Kirk and McCoy discover the one true cure for the Elasian tears - prior infection - in Kirk's case, the starship Enterprise had infected him even more powerfully than had the Dohlman.
Elba II, a planet with a poisonous atmosphere, also has a facility beneath its surface for the incurably, criminally insane. The U.S.S. Enterprise is bringing a new medicine with which they hope to eliminate mental illness forever.Review
When Kirk and Spock beam down to the facility of 15 inmates, they find that the asylum has been taken over by Garth of Izar, who was once a famous starship captain. He was driven insane by the terrible injuries he received while rescuing others. Garth convinces them that he is the head of the facility, in an attempt to gain control of the U.S.S. Enterprise and conquer the galaxy. He crowns himself, "Master of the Universe," and, when the officers won't be tricked into beaming him aboard the starship, he tortures Elba II's governor and then Kirk. He then sends his Orion mistress, Marta, out to the deadly surface above, only to "mercifully" spare her by blowing her to bits.
Spock, who had become separated from Kirk, returns to help the captain but finds two James Kirks. Garth learned the power of shape-shifting from a gentle race of beings that were unaware of his madness. When one of the Kirks offers to sacrifice himself to stop Garth, Spock realizes that this is the real Captain Kirk and subdues Garth. Garth is given the healing medication brought by the Enterprise crew and begins the long road to recovery.
The U.S.S. Enterprise intercepts a stolen Federation shuttlecraft which contains a humanoid named Lokai. Taken aboard the ship, Lokai tells the crew he is from the planet Cheron, and asks for asylum on the U.S.S. Enterprise. His most distinctive feature is that he is half black and half white, starkly separated down the middle of his body.Review
The U.S.S. Enterprise tracks another vessel, pursuing at great speed. The ship's only passenger beams on board and is discovers to be another humanoid from Cheron. The difference in this man, Bele, is that his black and white skin is reversed from Lokai's. Bele claims to be Cheron's chief officer sent out to bring in political traitors, and has been pursuing Lokai. The more the two men are aboard the starship, the more Kirk realizes that the basic problem between them - and their entire race, apparently - is their opposite color. Tiring of their bigotry, Kirk decides to ignore the two guests and concentrate on his original mission; to decontaminate the planet Ariannus, plagued with a bacteria that endangers billions of lives.
When Bele takes control of the U.S.S. Enterprise in a desperate attempt, Kirk sets the ships auto-destruct sequence instead of allowing the hijacking to continue, and the alien returns command to the captain. However, once planet Ariannus is decontaminated, Bele takes back his control over the starship and leads it back to Cheron. What they find is a long-dead planet, annihilated by their interracial bigotry. Lokai beams down to the surface to escape Bele, who follows. The U.S.S. Enterprise leaves them on the surface, to decide their own fates.
The planet Gideon appears to be a haven - the inhabitants are healthy and no one seems to ever die in the totally germ-free environment.Review
The United Federation of Planets sends the U.S.S. Enterprise to Gideon, in the hope that the Gideons will accede and become a member. Reluctantly, the Gideon council allows Captain Kirk alone to beam to their council chamber, and he transports off the ship. When Kirk apparently fails to arrive on the planet, the Gideon council refuses to allow more people on the surface, even for a search party.
Kirk finds himself on his own ship, where all of his crew have seemingly vanished. After searching the ship, he finds one lone, beautiful woman, Odona. Kirk determines that Odona is from Gideon, and that they are on a false ship, built on the planet's surface. When Odona becomes ill, the Gideon's plan is revealed: using Kirk's blood, Odona was infected with a disease which Kirk had recovered from - Vegan choriomeningitis. The infection is fatal, and the Gideons hoped to spread it across their world to reduce the population.
Spock beams down, discovers the false Enterprise, and returns to the real starship with Kirk and Odona, who - while cured - is still able to infect her people. Odona, the daughter of Gideon Council leader Hodan, is returned to her people delighted that she will cause a lethal plague to reduce the overpopulation.
As a landing party prepares to beam down to a previously unexplored Class-M planet, a beautiful woman, Losira, appears. She touches an ensign and kills him. Already dematerializing in the transporter beam, Kirk and the rest of his party are helpless to stop her. Losira then disappears.Review
The surge of power that Losira's appearance caused hurtles the U.S.S. Enterprise 990.7 light years away from where they were. Spock calculates that it will take 11.33 hours at warp 8.4 to return to the planet.
On the surface of the planet, Kirk, McCoy, Sulu and geologist D'Amato discover the vegetation is poisonous to humans and the rocks are made of an alloy that did not develop naturally. Losira appears again and kills D'Amato, again, by merely touching him. She vanishes, then reappears, this time for Sulu, but he avoids her and they realize she can only harm the person whose name she calls.
Kirk, Sulu and McCoy band together to keep her from killing them. Losira reappears on the Enterprise, in engineering, and kills another crewman. When Scotty insists that something "feels" wrong with the ship, they discover that Losira had sabotaged the matter/antimatter integrator. Scotty repairs the device before it has a chance to explode.
On the planet's surface, the landing party finds a chamber in the rocks that houses a computer. They realize that this is where Losira appears from. Losira appears to them again, this time in threes, so that she can touch each officer at once.
Spock and a security team arrive and destroy the computer that was projecting Losira's image. A visual recording triggered by the computer shows that the planet was once an outpost of the Kalandan race. It was ravaged by a deadly organism which supply ships unknowingly carried back to their home world. With the computer destroyed, the last of the Kalandans' civilization is also dead.
The U.S.S. Enterprise's mission is to take Lieuenant Mira Romaine to Memory Alpha, the central library for the United Federation of Planets. There she will supervise the transfer of new equipment to the facility. Mr. Scott is immediately attracted to the pretty lieutenant, and the feelings are returned.Review
While in orbit, an energy storm destroys all the inhabitants of Memory Alpha, wiping its computer memory banks. As a result of the storm, Romaine can predict where the storm will strike next; the Enterprise.
Despite evasive tactics by the starship, the storm enters the Enterprise where it is seen as brilliantly flashing colored lights. The lights enter Lieutenant Romaine and there is no way to remove them without killing the officer. Perusal of her file reveals a high susceptibility to empathic transmissions, making her an excellent home for the lights. The lights turn out to be non-corporeal entities from the long-dead planet, Zetar. They maintain that they have the right to inhabit Romaine's body, but Kirk doesn't agree. When Mira is placed in a pressure chamber, the Zetars, who are used to the vacuum of space, die. Lieutenant Romaine is free and presumably returns to Memory Alpha to help rebuild the great library.
Rigellian fever, an extremely deadly plague, strikes the U.S.S. Enterprise crew. Kirk, Spock and McCoy beam down to a supposedly uninhabited planet, Holberg 917-G, in search of the only known antidote, ryetalyn. To their surprise, they encounter Flint and his daughter, Rayna. Not pleased to have visitors, Flint orders his robot to gather and process ryetalyn, while the three officers are entertained by his daughter. Due to the robot contaminating the first batch of antidote, McCoy tells it another must be made. In the meantime, Kirk and Rayna have become attracted to each other, to Flint's jealous objection.Review
Spock has discovered, to his puzzlement, old masterpieces on modern supplies, i.e. a da Vinci painting done with modern oils on new canvas and an unknown Brahms waltz, written on new paper. Flint explains that he is an immortal, who wandered the Earth for centuries in various personas, including Brahms and da Vinci. He came to this planet to retire in peace and built the "Rayna" android as his companion. He had hoped that her involvement with Kirk would speed up her emotional growth, but now he has become hopelessly jealous. Not understanding such intense emotions, Rayna short-circuits and "dies."
The landing party takes the ryetalyn and returns to the Enterprise. McCoy tells them that Flint, too, will soon perish because what made him immortal was the atmosphere of Earth. Leaving it robbed him of that power.
In a surprisingly compassionate gesture, Spock uses a Vulcan mind touch to erase the painful memories of Rayna from Kirk's mind.
Chasing the stolen vessel Aurora, the U.S.S. Enterprise rescues the thieves just before the Aurora is destroyed. The group is led by Dr. Sevrin in a search for a mythological planet named Eden, a planet reputed to be a paradise.Review
Since one of Sevrin's group is the son of a Federation ambassador, Sevrin is held in protective custody while his followers are permitted to be free aboard ship. But when Spock is able to deduce Eden's location, Sevrin's followers free Sevrin and take over the starship.
Reaching Eden, Sevrin takes his people down to the surface in a shuttlecraft. When Kirk leads a landing party in pursuit, they find that the planet's vegetation all secretes deadly acid, and the fruits are all poisonous. Madly refusing to believe Kirk, Sevrin bites a piece of fruit and dies immediately. With his death, his followers are taken back aboard the U.S.S. Enterprise.
The U.S.S. Enterprise comes to the planet Ardana to acquire zienite, a rare mineral needed to stop a planet-wide plague on Merak II. The zienite is not available, however, because the miner class Troglytes are rebelling against the rulers of Ardana, who live in the cloud-city of Stratos.Review
The Stratos-dwellers insist that the Troglytes are naturally inferior beings, but Kirk discovers that the Troglytes are being affected by a gas emitted during mining.
Unable to get both sides to settle their differences, Kirk traps the Troglyte leader Vanna and the High Advisor of Ardana's Ruling Council, Plasus, inside a mine. When the gas takes effect, Plasus realizes what is happening and promises to help the Troglytes. With peace restored, the U.S.S. Enterprise is able to secure the zienite it needs.
The U.S.S. Enterprise is scanned by a powerful energy source coming from the planet Excalbia. The starship had been sent to survey the planet, but it was thought to consist of nothing but a lavalike surface without inhabitants.Review
The image of Abraham Lincoln appears in space and requests to be beamed aboard, claiming to be the genuine Lincoln. Against McCoy's objections, Kirk and Spock beam the entity aboard. They accept his offer to visit Excalbia, where a rock-like creature named Yarnek appears. Yarnek declares that the Enterprise officers are to participate in a battle between good and evil. This is to teach the Excalbians about humanoid concepts. Fighting for the "good" are, Kirk, Spock, Lincoln and Surak, founder of the present Vulcan culture. On the "bad" side are, Genghis Khan, Colonel Green, Zora - a vicious killer, and Kahless, father of the Klingon Empire as it was now known.
When the Enterprise officers refuse to fight, Yarnek freezes the starship's engines, starting a breakdown of the matter/antimatter shielding. If Kirk doesn't win, the ship will explode in four hours. There is much plotting and counter-plotting, until only Kirk, Spock, Khan and Zora remain alive. After some philosophical discussion regarding "good" and "evil," Yarnek returns Kirk and Spock to the U.S.S. Enterprise and frees the ship.
The crew of the U.S.S. Enterprise investigate the planet Sarpeidon whose sun is soon to go nova. Upon beaming to the surface, Kirk, Spock, and McCoy discover the inhabitants gone and a library containing the planet's accumulated knowledge.Review
Kirk, Spock and McCoy are surprised to find a lone inhabitant on the surface, Mr. Atoz, the librarian, who mistakes them for citizens of Sarpeidon. Mr. Atoz has been transferring people into the planet's past using a machine called the "atavachron." While investigating this unique technology, Kirk leaps to rescue a woman he hears screaming and ends transported to a period fraught with superstitions and witchcraft. Attempting to follow Kirk, Spock and McCoy enter the atavachron's portal to find themselves in a different time - Sarpeidon's ice age.
McCoy, who is close to freezing to death, and Spock are rescued by a beautiful woman, Zarabeth. While close to the portals they entered from, Kirk, Spock and McCoy can communicate with each other but little more. However, this is enough to get Kirk arrested for practicing witchcraft.
Spock increasingly finds himself attracted to Zarabeth, and disturbingly more emotional and irrational, and even goes against Vulcan custom by eating meat. McCoy convinces Spock that this time in Sarpeidon's past is linked to Vulcan's primitive past and that they must return to their own time. Zarabeth insists they cannot return to the present without dying.
In jail, Kirk is befriended by a lawyer, another traveler of Sarpeidon's present, who helps him escape to find the portal, and return to the library.
Zarabeth helps McCoy and Spock to the place where she found them. By following the sound of Kirk's voice, they find their portal and leap back into the library. Mr. Atoz leaps to his own designated past and the Enterprise, with Kirk, Spock, and McCoy safely aboard, warps from orbit just as the sun explodes.
Dr. Janice Lester, who was once involved with Captain Kirk, harbors a deep hatred of the captain, because she, herself, has never been able to captain a starship. On their way to Beta Aurigae, the U.S.S. Enterprise receives a call for help from Camus II. The landing party finds only Janice Lester and Dr. Coleman, who claim that the everyone else was killed by celebium radiation. In fact, Janice is quite ill from it.Review
Unaware of Lester's feelings of hatred toward him, Kirk sits with her, recalling their days together. Kirk is suddenly trapped into a life-entity transfer with Janice. His personality is in her body, while she takes over his, finally becoming captain of a starship. Kirk, with Janice's essence, tries to kill her victim, but fails. McCoy transports Janice, with Kirk's essence, to sickbay to try and treat her illness. While Kirk, trapped in Janice's body, tries to convince everyone that he's really the captain, Janice takes control of the ship and diverts it to the Benecia Colony. There she plans to leave her body, that houses Kirk's essence, thereby eliminating all her problems.
The crew becomes suspicious of her actions and, when Spock tries to question her, she charges him with mutiny. They realize something is wrong and Janice/Kirk is relieved of duty. When the transfer weakens and finally breaks, Kirk returns to his body, as Janice's essence returns to hers. Janice makes a last attempt to hurt Kirk, then collapses. Dr. Coleman, in love with Janice, requests that he be allowed to care for her. The U.S.S. Enterprise and her crew return to their mission, with their rightful captain at the helm.