A cybernetic warrior from a post-apocalyptic future travels back in time to protect a 25-year old drifter and his future wife from a most advanced robotic assassin and to ensure they both survive a nuclear attack.
Enjoying a peaceable existence in 1885, Doctor Emmet Brown is about to be killed by Buford "Mad Dog" Tannen. Marty McFly travels back in time to save his friend.