The Enterprise is in danger when Janice Lester, one of Kirk's former lovers, steals his body.
Kirk, Spock and McCoy are trapped in two parts of another planet's past - a world threatened with destruction when its sun goes supernova.
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.
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.
The Enterprise picks up a group of space "hippies" looking for Eden.
The crew of the Enterprise encounter an immortal human in this science fiction variation on Shakespeare's The Tempest.
Strange incorporeal aliens threaten the Memory Alpha station and the Enterprise.
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.
A race of overpopulated aliens abduct Captain Kirk to solve their problem.
The Enterprise encounters two duo-chromatic and mutually belligerent aliens who put the ship in the middle of their old conflict.
Captain Kirk faces off with a demented shape-shifting starship captain determined to control the universe.
The USS Enterprise ferries a spoiled princess whose betrothal to a royal Troyian is hoped will bring peace to a star system at war.
While visiting a doomed planet, the landing party is subject to torturous experiments by powerful aliens.
Invisible "time-accelerated" aliens take over the Enterprise and attempt to abduct the crew for use as "genetic stock".
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.
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.
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.
An alien force drives the crew of the Enterprise into brutal conflict with the Klingons.
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.
The Enterprise travels with an alien ambassador whose appearance induces madness.
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.
An alien device on a primitive planet erases Captain Kirk's memory, and he begins a new life with the planet's indigenous people.
The crew of the Enterprise are on a secret mission to steal a Romulan cloaking device.
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.
