Star Trek VI: The Undiscovered Country (Paramount Pictures, 1991) is the sixth feature film based on the Star Trek science fiction television series. It is often referred to as ST6:TUC or TUC. It is the last of the films based solely on the original series cast and it presents their final mission together.

Star Trek VI was dedicated to the memory of Star Trek creator Gene Roddenberry, who never lived to see its release, having succumbed to cardiac arrest on October 24, 1991 at age 70 (he did, however, view and approve a version of the film two days before his death). The film earned two Academy Award-nominations, for Best Makeup and Best Sound Effects.

After an explosion on their moon, the Klingons have an estimated 50 years before their ozone layer is completely depleted, and they all die. They have only 1 choice - to join the Federation, which will mean an end to 70 years of wars. Admiral James T. Kirk and crew are called upon to help in the negotiations because of their "experience" of the Klingon race. Peace talks don't quite go to plan, and eventually Kirk and McCoy are tried and convicted of assassination, and sent to Rura Penthe, a snowy hard-labour prison camp. Will they manage to escape ? And will there ever be peace with the Klingons ? Written by Colin Tinto

The Enterprise leads a battle for peace. After years of war, the Federation and Klingon empire prepare for a peace summit. But the prospect of intergalactic glasnost with sworn enemies is an alarming one to Captain Kirk. "They're animals!" he warns. When a Klingon ship is attacked and the Enterprise is held accountable, the dogs are war are unleashed again, as both worlds brace for what may be their final, deadly encounter. Written by Robert Lynch

It's all for one and one for all as the Kirk and the crew of Enterprise-A set course for the stars in their final adventure. The Klingon Empire has been one of the Federation's deadliest enemies for nearly a century. All of that changes when their key energy production facility, the moon Praxis, explodes, damaging the Klingon home world's atmosphere and meaning that all ozone will be depleted in 50 years. Unable to the cope with this disaster due to their massive military expenditures, the Empire seeks peace talks with the Federation in order to receive aid. Kirk however is opposed to the peace talks; it has been eight years since his son David was killed at the Genesis planet and he has never been able to forgive the Klingons for it. But he is a Starfleet officer and must escort Kronos One, the ship carrying Klingon Chancellor Gorkon, to Earth. But while en route, Kronos One is fired upon and Gorkon is assassinated. All evidence points to the Enterprise-A as the source of the photon torpedoes and Kirk and McCoy as the assassins, who are subsequently arrested, tried, and sentenced to life at the gulag Rura Penthe. But Spock is certain that Kirk and the Enterprise-A have been framed and with the aid of senior staff as well as help from Sulu, now captain of the Excelsior, set out to clear Kirk's name and cement a lasting peace between the United Federation of Planets and the Klingon Empire before all is too late. Written by Moriarty1701@aol.com

An accident on the Klingon moon Praxis forces the reluctant Klingon Empire into a peace treaty with the Federation. Kirk, despite his mistrust of the Klingons after they murdered his son at Genesis, is forced to escort a Klingon cruiser carrying the Klingon Chancellor to Earth for the meetings. During the voyage the Klingon cruiser is attacked, and Kirk & McCoy are taken prisoner after the Chancellor is murdered by two Starfleet crewmen. Spock immediately begins an investigation, while Kirk & McCoy are sentenced to life on Rura Penthe - a deep-frozen asteroid. Spock, meanwhile, has discovered that a Klingon Bird of Prey - one that can fire when cloaked, and under the command of Kingon General Chang - is the ship responsible for firing on the Chancellor, and the 2 assassins came from the Enterprise. A rescue of Kirk & McCoy is successful, after which they discover a conspiracy among Starfleet, Klingon, and Romulan officials whose plan is to incite a full-blown war! The Enterprise & Excelsior - under the command of Hikaru Sulu - head for a deadly rendezvous with General Chang at the peace summit to prevent war from breaking out...but will they be too late? Written by Derek O'Cain