James Kirk and the rest of the Enterprise crew reunite to destroy a new enemy that is threatening Earth and the human race.

Captain Kirk must destroy the Mercaniad, the sun of the planet Mercan, but in doing so would kill the citizens of Mercan.

Sabotage aboard the Enterprise and Spock's investigation lead him into defiance of the Federation and a bizarre alliance with the Romulan and Klingon Empires against the blood thirsty Tomarii.

The fate of the galaxy and the lives of three people depend on the outcome of the love triangle between Captain Kirk, Spock, and Sola Than.

Crew members of the Enterprise have strange experiences when an experimental engine takes over from warp drive. Use of the new engine may be damaging the universe.

A sentient force of protostars has taken control of a stranded team of Vulcan scientists. The Enterprise has come on a rescue mission with a female reporter and a computer that can override Kirk's commands, only to discover they must save themselves as well.

Captain Kirk unites with his old enemy Ael t' Rlailiiu, a Romulan commander, to destroy the laboratory that is genetically harnessing the mind power of Vulcans.

Composer Guy Maslin joins the crew of the "Enterprise" to investigate the strange continuous song of the inhabitants of Taygeta, source of a dangerous spacewarp, and they discover that the destruction of the Singers is linked to the growing discontinuity.

Kirk and McCoy accompany Spock to the Vulcan Academy Hospital, seeking treatment for an Enterprise crew member. Kirk soon finds himself involved in a homicide case.