• Air date: 20 Sep '68 24 episodes
      The third and final season of the original Star Trek aired Fridays at 10:00-11:00 pm on NBC from September 20, 1968 to March 14, 1969. The final episode aired Tuesday, June 3, 1969 at 7:30-8:30 pm.
  • List of Episodes (24)
    • 1. Spock's Brain

      20 Sep '68
      An alien female beams aboard the ship and, after incapacitating the rest of the crew, surgically removes Spock's brain. Kirk and the crew have just hours to locate and replace it before Spock's body dies.
    • 2. The Enterprise Incident

      27 Sep '68
      The crew of the Enterprise are on a secret mission to steal a Romulan cloaking device.
    • 3. The Paradise Syndrome

      04 Oct '68
      An alien device on a primitive planet erases Captain Kirk's memory, and he begins a new life with the planet's indigenous people.
    • 4. And the Children Shall Lead

      11 Oct '68
      On a distant planet, Kirk, Spock and McCoy find a scientific team dead, and their children who, unknown to the crew, have great powers at their disposal.
    • 5. Is There in Truth No Beauty?

      18 Oct '68
      The Enterprise travels with an alien ambassador whose appearance induces madness.
    • 6. Spectre of the Gun

      25 Oct '68
      Having been found trespassers into Melkotian space, Captain Kirk and his companions are sent to die in a re-enactment of the gunfight at the O.K. Corral.
    • 7. Day of the Dove

      01 Nov '68
      An alien force drives the crew of the Enterprise into brutal conflict with the Klingons.
    • 8. For the World Is Hollow and I Have Touched the Sky

      08 Nov '68
      The crew of the Enterprise rush to stop an asteroid from colliding with a Federation world, but discover the asteroid is actually an inhabited generation ship.
    • 9. The Tholian Web

      15 Nov '68
      Captain Kirk is caught between dimensions while the crew of the Enterprise works to retrieve him. All the while, the Tholians demand that the Enterprise leave their space.
    • 10. Plato's Stepchildren

      22 Nov '68
      The crew of the Enterprise encounters an ageless and sadistic race of humanoids with the power of telekinesis and who claim to have organized their society around Ancient Greek ideals.
    • 11. Wink of an Eye

      29 Nov '68
      Invisible "time-accelerated" aliens take over the Enterprise and attempt to abduct the crew for use as "genetic stock".
    • 12. The Empath

      06 Nov '68
      While visiting a doomed planet, the landing party is subject to torturous experiments by powerful aliens.
    • 13. Elaan of Troyius

      20 Dec '68
      The USS Enterprise ferries a spoiled princess whose betrothal to a royal Troyian is hoped will bring peace to a star system at war.
    • 14. Whom Gods Destroy

      03 Jan '69
      Captain Kirk faces off with a demented shape-shifting starship captain determined to control the universe.
    • 15. Let That Be Your Last Battlefield

      10 Jan '69
      The Enterprise encounters two duo-chromatic and mutually belligerent aliens who put the ship in the middle of their old conflict
    • 16. The Mark of Gideon

      17 Jan '69
      A race of overpopulated aliens abduct Captain Kirk to solve their problem.
    • 17. That Which Survives

      24 Jan '69
      Kirk, McCoy, and Sulu are stranded on a barren planet where a mysterious woman attempts to kill them one at a time, while the Enterprise must travel halfway across the galaxy to rescue them.
    • 18. The Lights of Zetar

      31 Jan '69
      Strange incorporeal aliens threaten the Memory Alpha station and the Enterprise.
    • 19. Requiem for Methuselah

      14 Feb '69
      The crew of the Enterprise encounter an immortal human in this science fiction variation on Shakespeare's The Tempest.
    • 20. The Way to Eden

      21 Feb '69
      The Enterprise picks up a group of space ""hippies"" looking for Eden.
    • 21. The Cloud Minders

      28 Feb '69
      Captain Kirk races against time to acquire plague-fighting minerals from a world in the midst of a civil uprising against a grievous social class disparity.
    • 22. The Savage Curtain

      07 Mar '69
      Aliens force Captain Kirk and First Officer Spock to join forces with "Abraham Lincoln" and "Surak" to battle villains in a contest of good vs. evil.
    • 23. All Our Yesterdays

      14 Mar '69
      Kirk, Spock and McCoy are trapped in two parts of another planet's past—a world threatened with destruction when its sun goes supernova.
    • 24. Turnabout Intruder

      03 Jun '69
      The Enterprise is in danger when Janice Lester, one of Kirk's former lovers, steals his body.