A mutant from more than half a century into the future, named Bishop, arrives in the present, attempting to change history for the better, by stopping an X-Man from committing an assassination. But between being chased by a future breed of Sentinel, and the details of his mission being fuzzy, he's got his work cut out for him.

Prominent anti-mutant and presidential hopeful Senator Kelly is caught in a tug-of-war between Magneto's goal of mutant superiority, the X-Men's dream of peaceful co-existance between mutants and humans, and the mutant-hunting Sentinel robots' goals of global domination.