On a desperate rescue mission to recover their missing captain, the shuttle Copernicus and its crew have become lost in time and space, transported by a powerful subspace vortex to a hellish future time line where the brutal Gorn Hegemony has all but conquered the United Federation of Planets. Stranded on a transformed Federation colony, now a Gorn mining world worked by oppressed human slaves, Helmsman Hikaru Sulu meets an older version of a man he barely knows, Pavel Chekov, who now leads a ragtag band of freedom fighters against the Gorns.

Teamed together for the first time, Sulu and Chekov must struggle to survive in a future that should never have happened!