Marty and Doc are at it again in this wacky sequel to the 1985 blockbuster as the time-traveling duo head to 2015 to nip some McFly family woes in the bud. But things go awry thanks to bully Biff Tannen and a pesky sports almanac. In a last-ditch attempt to set things straight, Marty finds himself bound for 1955 and face to face with his teenage parents -- again.

Collegian Tree Gelbman wakes up in horror to learn that she's stuck in a parallel universe. Her boyfriend Carter is now with someone else, and her friends and fellow students seem to be completely different versions of themselves. When Tree discovers that Carter's roommate has been altering time, she finds herself once again the target of a masked killer. When the psychopath starts to go after her inner circle, Tree soon realizes that she must die over and over again to save everyone.