First Officer Spock returns to his home world for a brutal Vulcan mating ritual.

The crew of the Enterprise visits a mysterious paradisical planet controlled by a computer that is served by the local inhabitants.

Two powerful aliens threaten the well-being of the Enterprise and her crew.

The Enterprise must transport dignitaries to a peace conference, with an assassin on the loose.

The crew of the Enterprise become entangled in a planet's tribal power struggle.

Strange radiation exposes the command crew of the Enterprise to the effects of rapid aging.

Captain James T. Kirk becomes obsessed with destroying a deadly entity he once encountered in his youth.

A series of bizarre murders points to Mr. Scott as the prime suspect.

The Enterprise must protect a very important shipment of grain from both Klingons and some adorable creatures called tribbles.

The crew of the Enterprise encounters an energy-draining field which may be able to destroy the galaxy.

The crew of the Enterprise tracks down a Federation observer on a planet dominated by a "Naziesque" regime.

Beings from another galaxy commandeer the Enterprise in an attempt to return home.

Captain Kirk must find the cure to a deadly disease and put an end to another Starfleet captain's cultural interference.