Theorizing that one could time travel within the last eight minutes of someone else’s lifetime, Captain Colter Stevens stepped into the Quantum Leap accelerator and vanished.  He awoke to find himself trapped on a train, facing a mirror image that was not his own and driven by an unknown bomb to blow up in a violent explosion.  Now, Captain Stevens must continue re-living those eight minutes until he can figure out who planted the bomb and prevent him from detonating a meaner, dirtier nuclear bomb in the present. 

All Quantum Leap jokes aside...