Back to the Future Part II
Back to the Future Part II is a 1989 American science fiction film directed by Robert Zemeckis and written by Bob Gale. It is the sequel to the 1985 film Back to the Future and the second installment in the Back to the Future trilogy. The film stars Michael J. Fox, Christopher Lloyd, Lea Thompson, and Thomas F. Wilson. The film follows Marty McFly (Fox) and his friend Dr. Emmett "Doc" Brown (Lloyd) as they travel from 1985 to 2015 to prevent Marty's son from sabotaging the McFly family's future; when their arch-nemesis Biff Tannen (Wilson) steals Doc's DeLorean time machine and uses it to alter history for his benefit, the duo must return to 1955 to restore the timeline.
On October 26, 1985, Dr. Emmett Brown arrives in the DeLorean time machine and persuades Marty McFly and his girlfriend, , to travel to the future with him and help their future children, with Biff Tannen witnessing their departure. They arrive on October 21, 2015, where Doc electronically incapacitates Jennifer and leaves her asleep in an alley, explaining that she should not have too much knowledge of future events. He has Marty pose as his own son and lookalike Marty Jr. to refuse an offer to participate in a robbery with Biff's grandson Griff, thus saving Marty Jr. from prison.