

All episodes — Season 3
S3 E1Spock's Brain
Sep 20, 19686.151 min
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.
S3 E2The Enterprise Incident
Sep 27, 19687.951 min
The crew of the Enterprise are on a secret mission to steal a Romulan cloaking device.
S3 E3The Paradise Syndrome
Oct 4, 19686.651 min
An alien device on a primitive planet erases Captain Kirk's memory, and he begins a new life with the planet's indigenous people.
S3 E4And the Children Shall Lead
Oct 11, 19685.851 min
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.
S3 E5Is There in Truth No Beauty?
Oct 18, 19687.151 min
The Enterprise travels with an alien ambassador whose appearance induces madness.
S3 E6Spectre of the Gun
Oct 25, 19686.851 min
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.
S3 E7Day of the Dove
Nov 1, 19687.551 min
An alien force drives the crew of the Enterprise into brutal conflict with the Klingons.
S3 E8For the World Is Hollow and I Have Touched the Sky
Nov 8, 19687.151 min
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.
S3 E9The Tholian Web
Nov 15, 19687.550 min
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.
S3 E10Plato's Stepchildren
Nov 22, 19686.951 min
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.
S3 E11Wink of an Eye
Nov 29, 19687.451 min
Invisible "time-accelerated" aliens take over the Enterprise and attempt to abduct the crew for use as "genetic stock".
S3 E12The Empath
Dec 6, 19686.551 min
While visiting a doomed planet, the landing party is subject to torturous experiments by powerful aliens.
S3 E13Elaan of Troyius
Dec 20, 19686.851 min
The USS Enterprise ferries a spoiled princess whose betrothal to a royal Troyian is hoped will bring peace to a star system at war.
S3 E14Whom Gods Destroy
Jan 3, 19696.951 min
Captain Kirk faces off with a demented shape-shifting starship captain determined to control the universe.
S3 E15Let That Be Your Last Battlefield
Jan 10, 19697.451 min
The Enterprise encounters two duo-chromatic and mutually belligerent aliens who put the ship in the middle of their old conflict.
S3 E16The Mark of Gideon
Jan 17, 19696.751 min
A race of overpopulated aliens abduct Captain Kirk to solve their problem.
S3 E17That Which Survives
Jan 24, 19696.651 min
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.
S3 E18The Lights of Zetar
Jan 31, 19696.651 min
Strange incorporeal aliens threaten the Memory Alpha station and the Enterprise.
S3 E19Requiem for Methuselah
Feb 14, 19697.151 min
The crew of the Enterprise encounter an immortal human in this science fiction variation on Shakespeare's The Tempest.
S3 E20The Way to Eden
Feb 21, 19696.251 min
The Enterprise picks up a group of space "hippies" looking for Eden.
S3 E21The Cloud Minders
Feb 28, 19697.151 min
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.
S3 E22The Savage Curtain
Mar 7, 19696.751 min
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.
S3 E23All Our Yesterdays
Mar 14, 19697.951 min
Kirk, Spock and McCoy are trapped in two parts of another planet's past - a world threatened with destruction when its sun goes supernova.
S3 E24Turnabout Intruder
Jun 3, 19697.151 min
The Enterprise is in danger when Janice Lester, one of Kirk's former lovers, steals his body.