Cage, The
Kirk's predecessor Captain Christopher Pike, tries to rescue an earth crew that disappeared 18 years earlier, and finds himself trapped in an alien "zoo". This episode was the original pilot for the Star Trek series but was rejected by NBC because it was "too cerebral" and NBC wanted to make some changes, namely: the satanic-looking guy with the ears had to go (he didn't) and a woman wasn't allowed to be second in command.
Where No Man Has Gone Before
The Enterprise nears a magnetic barrier at the edge of the galaxy, and Kirk's friend Lt. Gary Mitchell is mutated. His emerging powerful ESP abilities threaten the safety of the ship.
Carbomite Manuever, The
When the Enterprise encounters and destroys a radioactive cube, a gigantic ship appears, and the Enterprise crew is sentenced to death by a mysterious alien called Balok.
Mudd's Women
The Enterprise rescues a ship's crew at the expense of all but one of their dilithium crystals. The "captain" of the destroyed ship is space pirate Harry Mudd, the cargo: three beautiful women who hypnotise the men around them.
Enemy Within, The
A malfunction of the transporter slips Kirk into separate beings: one bestial, the other rational and sensitive.
Man Trap, The
Making a routine medical stop at planet M113 proves fatal for several crew members, with every ounce of salt mysteriously removed from their bodies.
Naked Time, The
A research team on Psi 2000 is due to be evacuated, but the Enterprise finds the scientists dead. The germ from the scene is transmitted to the crew, causing a disturbing surfacing of suppressed emotions.
Charlie X
The lone survivor of a crash on the planet Thasus 14 years ago is transferred to the Enterprise by the Antares, whose crew seem eager to leave him. Suddenly the Antares is destroyed, and Charlie begins to display a power he cannot control.
Balance of Terror
Can Kirk outwit the Romulan commander who has destroyed Federation outposts from an invisible ship?
What are Little Girls Made Of
The U.S.S. Enterprise hails Expo III in search for the eminent biologist, Dr. Roger Korby. To everyone's surprise, Korby gladly responds to the Enterprise, inviting Kirk to beam down. Kirk finds out that Korby plans to duplicate people as androids so that war, strife and unhappiness can be programmed out of people and his first victim is to be Kirk.
Dagger of the Mind
During a stop at a penal colony on Tantalus Five, an inmate escapes to the Enterprise. He's found to be the assistant to the colony's director, Dr. Adam's, and tells of a painful "neural neutralizer" employed by Dr. Adam's. The Vulcan mind-meld is introduced here providing nice insight into the Vulcan culture.
Miri
This tale of a world inexplicably a duplicate of Earth, where adults tried to stop ageing only to unleash a plague that would reduce the world's population to just children. Kirk and crew find that this world's children ageing a month every century. What is known to the children is that when they reach a certain age, they will contract a horrible deadly disease that strikes the landing party as soon as they beam down.
Consience of the King, The
A touring Shakespeare company comes aboard the Enterprise but one of the actors seems familiar and it is possible that he is a former governor of Taarsus IV who ordered the execution of countless innocents that planet 20 years before. Two Tarsus survivors are aboard the ship and the actors daughter Lenore wants to kill all the survivors in a pathetic and insane attempt to shield her father from the past.
Galileo Seven, The
When Spock, McCoy and Scotty crash land on Taurus II in the shuttle craft, Spock must fight alien creatures and attempting to reach logical command decisions results in the death of several men. McCoy is a constant thorn in the first officer's side as the doctor challenges the wisdom and effectiveness of the Vulcan's rational approach to an irrational world.
Court-Martial
The Enterprise takes a beating during an ion storm and an officer enters the ion pod to take readings. When the storm makes it imperative to jettison the pod, the officer dies, and Kirk faces court-martial for negligence. Cook's performance his wonderful as the outer space lawyer Samuel T. Cogley.
Menagerie, The
The Menagerie is one of the series most memorable stories, it incorporates footage from the first Star Trek pilot "The Cage". For reasons unknown Spock kidnaps Captain Pike, his former commander and then hijacks the U.S.S Enterprise and sets them on course for the forbidden Talos IV.
Shore Leave
Captain gives the fatigued crew a brake from duty on an earth-like planet, but encounters with a giant white rabbit, Samurai warrior, tigers, swordsmen, and a deadly black knight prove less than relaxing. This show features -between Kirk and Finnegan- the longest fight sequence in the series if not in the history of television.
Squire of Gothos, The
The fun begins when the Enterprise encounters a strange planet and its even stranger inhabitant, a being dressed like an old English lord of the manor. He promptly kidnaps an assortment of crew members with which to populate his historical fantasies. Kirk's attempts to reason with Trelane or bargain for freedom make little headway against his manic romping and awesome powers.
Arena
When the U.S.S. Enterprise pursues Gorn vessel that attacked a Federation outpost, both ships enter the territory of the Metron race, who deposit Kirk and the alien captain on an deserted planet to settle their conflict in single combat.
Alternative Factor, The
This episode explores the duality of man, a recurring theme in Star Trek. The crew encounters an odd man named Lazarus. It later become obvious that Lazarus is actually two distinct beings, each from a different dimension and each determined to destroy the other. As the Lazarus of the anti-matter universe passes through a dimensional portal, he causes an energy disruption that threatens the entire positive-matter universe.
Tomorrow is Yesterday
The Enterprise is shot into the 20th Century by a black star. Now Kirk has to erase evidence of their starship's unscheduled appearance, return one fighter pilot minus his memories of the peek at the future so his unborn son can lead a landmark space mission.
Return of the Archons, The
In this care, Kirk again outwits a computer, giving McCoy a chance to jib Spock about human emotions making all the difference in the galaxy. Visiting Beta III to learn the fate of the USS Archon, Kirk and crew find a populace strangely under control of a mystical ruler called Landru.
Taste of Armageddon, A
On Eminiar VII, Kirk finds a "war" has been fought for centuries with another planet through their computers. When a hit is declared, people willingly enter death chambers. Suddenly, Kirk is told that the Enterprise is declared "destroyed".
Space Seed
The USS Enterprise comes across the Botany Bay, a sleeper ship that contains the tyrannical Khan Noonien Singh, along with his followers. All of them were world conquerors, products of the Eugenics War of the 1990s and once dethawed, set about conquering the Enterprise.
This Side of Paradise
A surprise USS Enterprise finds survivors on Omicron Ceti III a planet bombarded by deadly Berthold rays. Not only are the colonists alive, they are thriving.. due to protective spores. The crew is sprayed with these spores and a personality change occurs and the entire crew seems to have found eternal happiness, leaving Kirk on a deserted ship.
Devil in the Dark, The
Pergium mining comes to a halt at a colony where miners are suddenly being killed by a creature who secrets acid and tunnels through rock. This episode gave us our first real glimpse of the Vulcan mind-meld used to tremendous effect as Spock reveals the anger and anguish of a creature driven to defend itself and its offspring against forces it doesn't understand.
Errand of Mercy
Kirk and Spock beam down to Organia and to warn of an oncoming invasion by the Klingons. Frustrated by the passive brush-off by the Oraganians, the captain and first officer are then stuck in the middle when the Klingons show up. The USS Enterprise officers wage a two-man guerrilla war against the invaders before the Organians reveal themselves to be ultra-powerful beings who force peace between the Enterprise and the Klingons.
City on the Edge of Forever, The
Accidentally injected with a drug that induces paranoid delirium, a crazed McCoy beams down to a planet where there is time disturbance and disappears into the past. The present is immediately altered, the Enterprise vanishes into non-existence. Kirk and Spock follow McCoy through time to 1930 New York, where they encounter Edith Keeler. Kirk falls in love with her only to learn that in order for history to be restored, she must die.
Operation: Annihilate!
Kirk finds his brother dead on the planet Denevam which is in the midst of an epidemic of mass insanity caused by creatures who attack the nervous system, causing unbearable pain to manipulate their victims.
Catspaw
The Enterprise encounters two people who use magical means to convince the humans that they're to be taken seriously when they say they are would be conquerors. While their powers play upon normal human superstitions, Spock remains singularly unaffected and oddly ignorant of the way the supernatural can affect humans fears. However their tricks prove to be nerve-wracking to Spock who must watch as first Sulu, the McCoy become zombies.
Metamorphosis
The Shuttlecraft Galileo is waylaid by a strange cloud while conveying the ailing Asst. Commissioner Hedford to the Enterprise, and brought to a planet where the only apparent inhabitant is a space pioneer thought long dead.
Friday's Child
The Enterprise visits Capella IV to stop the Klingons from making allies of the warlike natives. When Kirk saves the Capellan leader's wife he violates their traditions, and he, Spock and McCoy become hunted fugitives on the planet. In this episode McCoy utters another variation of his classic line: "I'm a doctor, not an escalator."
Who Mourns for Adonais?
A huge green hand appears in space and holds the Enterprise motionless. The crew is brought to Pollox IV, where a humanoid claiming to be the god Apollo wants the to stay, become shepherds, and spend their lives worshipping him.
Amok Time
Spock has entered a phase called Pon farr, the Vulcan mating cycle, and must return to Vulcan where he has been betrothed to T'Pring, his bride who is know more interested in another vulcan named Stonn. Spock must fight to be her mate. Unwilling to risk Stonn T'Pring chooses Kirk to be her champion and he accepts not realising this is a fight to the death.
Doomsday Machine, The
Commodore Matt Decker loses his crew, the men and women of the Constellation, to the planet-devouring appetite of the space-going ultimate weapon. With Kirk stuck aboard the helpless Constellation, Decker takes over the USS Enterprise. Finally, forcibly relieved of command by Spock (in the exchange that climaxes in the now-famous "Vulcans never bluff").
Wolf in the Fold
On Argelius II, where Chief Engineer Scott has taken shore leave a number of young women have been brutally murdered. Scott is circumstantially implicated, and an investigation follows-including an Argelian empathic ceremony with the eerie feel of a seance. Ultimately the real murderer is discovered to be an inhuman ancient life form that once manifested on Earth as Jack the Ripper.
Changeling, The
A probe named Nomad goes, through a mishap of programming, around obliterating all life forms not deemed "perfect". Upon encountering the Enterprise it mistakes James T. Kirk for Jackson Roykirk its creator and decides to return to Earth to sterilize that planet of imperfections. Apple, The
Kirk and a landing party Gamma Trianguli VI are plagued by lightning, exploding rocks and poisonous plants. The childlike inhabitants are ruled by Vaal, a computer which threatens the safety of the Enterprise and its crew.
Mirror, Mirror
Kirk, McCoy, Scott and Uhura are transposed by an ion storm-induced transporter malfunction to a parallel universe-a perversely savage version of the universe in which the USS Enterprise operates like a pirate ship within a brutal Galactic Empire. Most importantly they quickly realise that their chances for short-term survival ride on their abilities to adjust instantly to this barbaric universe and keep their true identities hidden.
Deadly Years, The
Chekov discovers the dead body of an emaciated and greatly aged man on Gamma Hydra IV. All too soon Kirk and the officers show the same ominous signs of rapid ageing. Kirk Battles against a failing memory and the indignity of competency hearing that removes him from command. A desk-bound, paper-pushing commodore who takes charge of the bridge sends the starship blundering into the Romulan Neutral Zone.
I, Mudd
Harcourt Fenton Mudd stumbles on a planet full of androids just begging to serve and wanting to study him as a sample of Homo Sapiens. Harry brings a replacement sample, namely starship captain James T. Kirk. Then the androids announce their plan to use the Enterprise to go out and control humanity, which the androids see as an altogether self-destructive group of beings unable to run their own affairs.
Trouble with Tribbles, The
On space station K-7 Kirk has little patience for orders to protect a grain shipment or for the arrival of a group of Klingons. But the fast-multiplying, fluffy tribbles brought by a space trader turn out to be his biggest headache. Many will say that "Tribbles was one of the best episodes and one reason is that this one uses gentle humour driven by character to entertain.
Bread and Circuses
Seeking the lost crew of the Beagle the USS Enterprise trace them to a planet remarkably resembling olden-day Rome, complete with televised gladiatorial events. Naturally, Kirk, Spock and McCoy find a way to end in front of the arena themselves.
Journey to Babel
The Enterprise is assigned to ferry a valuable cargo of ambassadors. While a mysterious ship is following the Enterprise. Spock's father Sarek is on of the ambassadors and has a heart attack due to an illness and at the same time the Enterprise is attacked and Kirk seriously wounded. Spock's sense of duty will let his father die rather then risk the Enterprise.
Private Little War, A
On a pastoral planet, Klingons supply the Hill People with flintlock rifles and these weapons are used to attack the villagers led by the peaceful Tyree, whom Kirk had befriended. Kirk's dilemma: Do nothing, or re-establish a balance of power by supplying weapons to Tyree's people. This episode pretty much echoed US government justifications for intervention in Vietnam, something TV networks have never liked to do.
Gamesters of Triskelion, The
Kirk, Uhura and Chekov are abducted by a transporter beam which brings them to the planet Triskelion. There they are used a gladiators, fighting for the amusement of the planet's ruler.
Obsession
The title comes from the fact that the Captain encountered a cloud 11 years before. It killed the captain and half the crew of the USS Farragut. Now Kirk is determined to stop the cloud from doing the same to his crew.
Immunity Syndrome, The
The Enterprise encounters a gigantic, one-celled life form destroying everything in its path in need for life-sustaining energy. To stop it Spock enters the life form to seek out what is causing the creatures need for energy and cure it.
Piece of the Action, A
An Enterprise landing party checks on the progress of lotia, visited 100 years earlier by the USS Horizon. They find the Lotians live in imitation of the Chicago gangland mobs of the 1920s, based on a book left by a crew member.
By Any Other Name
A race called the Kelvans hijack the Enterprise for their return trip to their home in the Andromeda galaxy. They assume human form and the crew of the enterprise takes advantage of this by satisfying their various temptations of the flesh.
Return to Tomorrow
Answering an S.O.S. from a dead planet, the crew find three beings who have encased their minds in containers, and wish to "borrow" the bodies of Kirk, Spock and Dr. Anne Mulhall while building android bodies for themselves.
Patterns of Force
When the Enterprise arrives for a routine check of Ekos, they come under nuclear attack, and find that a Federation historian has violated the prime directive and inadvertently effected a chilling recreation of Nazi Germany.
Ultimate Computer, The
In spite of Kirk's misgivings. Starfleet allows a new computer, M-5 to control the Enterprise in a test with a reduced crew. During manoeuvres, the M-5 destroys another starship, and refuses to return control of the ship to Kirk.
Omega Glory, The
The Exeter is discovered orbiting Omega IV its crew turned to powder by a virus. Kirk, Spock and McCoy beam down to the planet's surface to discover the Exeter's captain has violated the prime directive in search of immortality.
Assignment: Earth
The Enterprise returns to Earth of the late '60s and encounter Gary Seven, an Earthling raised by mysterious aliens. Armed with a nasty little weapon he appears determined to cause a rocket mishap that will trigger WWIII. Kirk and Spock race to stop him, while realising that they're not in their correct era and could cause more harm than good.
Spectre of the Gun
Kirk ignores a "Space Buoy" warning marking the edge of Melkotian space. He and his officers are beamed to the Melkot planet to re-enact the deadly western gunfight at the OK Corral as their punishment.
Elaan of Troyius
Elaan is the Dohlman of Elas and she is being ferried to Troyius for a marriage intended to end centuries of war between the two populated worlds in a solar system near the Klingon Empire. The Enterprise is dogged by a Klingon battle cruiser and a spy the damages the Enterprise with the Klingons bearing down on them.
Paradise Syndrome, The
As an asteroid threatens a planet, a landing party beams down, finding a peaceful native culture. When Kirk vanishes, the others return to the ship, trying to save the planet, while Kirk is absorbed into the culture and married with Spock and McCoy at each others throat after having failed to rescue him.
Enterprise Incident, The
When Kirk enters Romulan space and is captured, he is denounced by Spock, who is urged to defect by the female Romulan commander.
And the Children Shall Lead
An evil entity has caused all the adults on Triacus to commit suicide, while their children are unharmed and strangely oblivious to the deaths of their parents. The entity sneaks aboard the Enterprise with the children. The children induce hallucinations on the crew with the power of the entity.
Spock's Brain
A mysterious woman renders the crew unconscious and steals Spock's brain and takes it to her planet and uses it to control the computer which controls the planet.
Is There in Truth No Beauty?
Dr. Miranda Jones escorts a Medusan, whose unprotected appearance can cause insanity in humans, aboard the Enterprise to conduct a peaceful experiment, which goes awry when her companion becomes jealous. This episode addresses "the last of our prejudices": Our preference for what our culture deems beautiful, our aversion to what our culture deems ugly.
Empath, The
Kirk, Spock and McCoy are seized while searching for lost researchers on a remote planet. Another prisoner, a mute empath named Gem, heals the wounds inflicted on them by the mysterious aliens who captured them.
Tholian Web, The
Spock is thrown into command when Kirk is lost in another dimension. Spock hopes to rescue Kirk during the next dimensional interphase despite the threats of a Tholian captain. Spock and McCoy face off in their most bitter confrontation in the series but are forced to work together after reading Kirk's prediction of their now current situation.
For the World is Hollow and I have Touched the Sky
Yonada is -unknown to its people- a really huge, hollow space ship sent out long ago to colonise a new planet, but is now on a collision course with an asteroid. Kirk, Spock and McCoy try to wrest control of the ship's malfunctioning computer before the crash.
Day of the Dove
The Enterprise and a Klingon ship chlas near Beta XII-A. Each side blames the other for opening hostilities, but the crew gradually realise that another force controls the battle, and is healing the wounded to prolong the fight.
Plato's Stepchildren
The Enterprise receives a call from the planet Platonius requesting medical help. After beaming down the crew discovers that the Platonians possess awesome telekinetic abilities and have no intention of allowing McCoy to leave. This episode featured network television's first interracial kiss.
Wink of an Eye
The Enterprise responds to a distress call from the planet Scalos. Events then prove that the Scalosians are invisible and are the survivors of a planetary disaster which left their world poisoned and their males sterile. The Enterprise is now kept on ice as a fertility bank.
That Which Survives
A geologically unstable planet draws Kirk and crew to the surface to investigate, where they encounter a beautiful woman whose touch can kill to protect a distant scientific outpost. The Enterprise is then hurled light years away, stranding the landing party.
Let That Be Your Last Battlefield
The Cheronians are half black, half white people and on the planet there is extreme racial prejudice which threatens to spark a civil war and both are pleading for the federations help.
Whom Gods Destroy
When Kirk and Spock beam down to deliver a wonder drug to the governor of an asylum for the criminally insane on Elba II, they find the inmates have taken over the asylum, and a force field prevents their own escape.
Mark of Gideon
Kirk beams down to the planet Gideon to recruit them into the Federation, but never arrives. He finds himself alone with a beautiful woman, Odona, and an empty Enterprise, while Spock initiates a frustrating search for the lost captain. This story mostly deals with another 1960s concerns, overpopulation.
Lights of Zetar, The
An energy storm destroys the scholars on Memory Alpha, a federation facility, then enters Lt. Mira Romaine's body, who becomes an unwilling host for the "lights." Kirk and crew try to exorcise this deadly life-force before it kills her.
Cloud Minders, The
An epidemic strikes the planet Merak II, and the Enterprise goes to Ardana in search of the cure. There they are caught in the middle of a class struggle between surface-dwelling miners and the ruling elite, who live in the clouds. Notably the guest star Jeff Corey was Nimoy's former acting teacher and a victim of the Hollywood blacklist.
Way to Eden, The
Kirk gives chase to a stolen ship, the Aurora, and rescues the crew before it explodes. A rebellious group of young idealists led by an ailing and insane Dr. Sevrin, they are searching for a mythical planet called Eden.
Requiem for Methuselah
The Enterprise needs a substance from Holberg 917-G to cure a Rigellian fever that has stricken the crew. On the planet Kirk, Spock and McCoy meet a lonely immortal named Flint. What concern them is the mysterious benefactor and his overprotective robot. Kirk then falls in love with Flints ward but Flint won't stand for it.
Savage Curtain, The
On Excalbia, the inhabitants have such a different morality that good and evil are unknown concepts. Therefore, they snatch the USS Enterprise and force its officers to participate in a contest with beings plucked from Federation history. On the planet they meet figures such as Abraham Lincoln, Genghis Khan and Surak, a Vulcan philosopher.
All Our Yesterdays
Sarpeidon's sun is about to go nova. The Enterprise goes there to warn the inhabitants, but discovering that they have already moved through a time portal to the planet's past. Hearing a cry from the portal Kirk steps into it landing in an medieval jail while McCoy and Spock land in a frozen ice age. Due to the time displacement Spock's long repressed emotions surge to the fore.
Turnabout Intruder
Dr. Janice Lester enacts a mind switch and takes over Kirk's body, depositing Kirk's mind in hers. In command she acts differently enough to arouse the ships's officers suspicions. This was the last Star Trek episode of the original series.