Season 1 Episodes
1. The Man Trap
Kirk and his crew are at deadly risk from an alien creature that feeds on the salt in a human body and can take on any form.
2. Charlie X
Charlie Evans, the sole survivor of a transport crash, is transferred to the Enterprise from a different ship. Why are they so eager to rid themselves of him, though? There's more to Charlie than meets the eye...
3. Where No Man Has Gone Before
While exploring the edge of the galaxy, the Enterprise encounters an energy barrier that gives some crewmen strange powers.
4. The Naked Time
A strange alien substance causes the crew to lose their inhibitions.
5. The Enemy Within
A transporter malfunction causes Captain Kirk to split into his "good" and "evil" selves, and a landing party will freeze to death if they don't merge the two back together.
6. Mudd's Women
The Enterprise picks up a intergalactic conman, Harry Mudd, and three incredibly beautiful women who harbor a dark secret.
7. What Are Little Girls Made Of?
Nurse Christine Chapel is reunited with her old fiance on Exo III, but the scientist has plans for Captain Kirk and the Federation.
8. Miri
Kirk and a landing party are stranded on a planet due to a disease that causes any adult to die a painful death, and must deal with the local children who have survived.
9. Dagger of the Mind
Kirk investigates an experimental facility for holding prisoners and finds a sinister scheme.
10. The Corbomite Maneuver
The Enterprise encounters a vast alien ship that threatens the Enterprise with destruction.
11. The Menagerie (1)
Spock kidnaps his former captain, the crippled Christopher Pike, and heads for a quarantined planet, putting his career and Kirk's life on the line.
12. The Menagerie (2)
Spock's court-martial continues as he attempts to justify his abduction of Pike, the theft of the Enterprise, and his heading for a planet declared forbidden by Starfleet.
13. The Conscience of the King
Kirk is one of the last survivors who can identify a mass killer, who lurks among a Shakespearean troupe aboard the Enterprise.
14. Balance of Terror
Kirk pits the Enterprise against an invisible spaceship testing the Federation's defenses.
15. Shore Leave
The Enterprise crew take shore leave on a peaceful, pastoral planet... where their dreams and fantasies come to life.
16. The Galileo Seven
Spock commands a stranded away team when their shuttlecraft is stranded on a planet with hostile natives.
17. The Squire of Gothos
The Enterprise finds itself at the mercy of a seemingly omnipotent being who fancies himself an 18th century Englishman.
18. Arena
When a mysterious alien race destroy an Earth colony, the Enterprise pursues, but Kirk and the alien captain are forced to fight each other by powerful aliens.
19. Tomorrow Is Yesterday
In a freak accident the Enterprise is sent back to 20th century Earth, and must find their way back without changing history.
20. Court Martial
Captain Kirk's career is at stake when he is put on trial for the loss of a crewman during an ion storm.
21. The Return of the Archons
The Enterprise encounters a seemingly peaceful civilization run by a "benevolent" being named Landru... who intends for them to join his people.
22. Space Seed
The Enterprise picks up a crew of genetic supermen from the 20th century... and their leader, Khan, plans to create a new empire.
23. A Taste of Armageddon
The Enterprise arrives at a planet to establish diplomatic relations and finds itself in the middle of a "peaceful" war that threatens to destroy the ship.
24. This Side of Paradise
The Enterprise crew try to rescue colonists from deadly radiation, but instead encounter strange alien spores that seem to offer paradise.
25. The Devil in the Dark
Kirk investigates a series of grisly murders on a mining planet that are the work of a seemingly hostile alien creature.
26. Errand of Mercy
The Federation and the Klingon Empire teeter on the brink of war as Kirk investigates Organia, a humble planet, inhabited by pacifists, that is unwittingly caught in the middle.
27. The Alternative Factor
Kirk and Spock encounter an alien named Lazarus who claims to be from an anti-matter universe.
28. The City on the Edge of Forever
Kirk and Spock must travel into the past in order to correct a change that will alter history.
29. Operation: Annihilate!
Kirk and the Enterprise must combat parasitic aliens threatening the lives of millions.