Space. The Final Frontier. The U.S.S. Enterprise embarks on a five year mission to explore the galaxy. The Enterprise is under the command of Captain James T. Kirk with First Officer Mr. Spock, from the planet Vulcan. With a determined crew, the Enterprise encounters Klingons, Romulans, time paradoxes, tribbles and genetic supermen led by Khan Noonian Singh. Their mission is to explore strange new worlds, to seek new life and new civilizations, and to boldly go where no man has gone before.
A transporter mishap swaps Captain Kirk and his companions with their evil counterparts in a parallel universe. In the so-called Mirror Universe, the Enterprise is a ship of the Terran Empire, an organization as evil as the United Federation of Planets is benevolent.