Six months after the events in Back to the Future Part III (1990), Marty McFly is adjusting to life without his best friend Doc Brown. As Doc left everything behind, the bank has foreclosed on his house and now his estate will be sold off, causing Marty to face the possibility that Doc will never return. Suddenly, the DeLorean time machine mysteriously appears out of nowhere. Marty learns that Doc has once again found himself stranded in another time period, and Marty must go back in time to rescue him.