Helicopter pilot Colter Stevens (Jake Gyllenhaal) is part of a top-secret military operation that enables him to experience the last few minutes in the life of Sean Fentress, a man who died in a commuter-train explosion. The purpose of Colter's mission is to learn the identity of the bomber and prevent a similar catastrophe. As Colter lives Sean's final moments, he becomes more certain that he can prevent the first tragedy from occurring -- as long as he doesn't run out of time.