Back to the Future is a 1985 American science fiction film directed by Robert Zemeckis and written by Zemeckis and Bob Gale. It stars Michael J. Fox as teenager Marty McFly, who accidentally travels back in time from 1985 to 1955, where he meets his future parents and becomes his mother's romantic interest. Christopher Lloyd portrays the eccentric scientist Dr. Emmett "Doc" Brown, his friend and the inventor of the time-traveling DeLorean automobile, who helps Marty repair history and return to 1985. The cast also includes Lea Thompson as Marty's mother Lorraine, Crispin Glover as his father George, and Thomas F. Wilson as Biff Tannen, Marty and George's arch-nemesis.
Zemeckis and Gale wrote the script after Gale wondered whether he would have befriended his father if they had attended school together. Film studios rejected it until the financial success of Zemeckis' Romancing the Stone. Zemeckis approached Steven Spielberg, who agreed to produce the project at Amblin Entertainment, with Universal Pictures as distributor. Fox was the first choice to play Marty, but he was busy filming his television series Family Ties, and Eric Stoltz was cast; after the filmmakers decided he was wrong for the role, a deal was struck to allow Fox to film Back to the Future without interrupting his television schedule.