Ben leaps into a priest who has been called to assist a family in crisis on Halloween night; as he delves into mysterious and inexplicable events, he's forced to muster all his resources as a scientist before time runs out.

When Ben leaps into one of five people in an elevator at a 1962 nuclear reactor, he must figure which one triggers a bomb that kills them all. Each time the bomb goes off, he leaps into another one of them an hour earlier, resetting the scene.

Ben’s next leap takes him closer to home than he ever expected. The team faces the ultimate showdown with Leaper X as they battle for the future of the Quantum Leap project and their lives.

Ben leaps back to 1692 -- the farthest he's ever been -- where he finds himself on trial for practicing witchcraft. With limited records online, the team must race to save him before he's put to death.