1956: The shy Jonathan's luck with girls changes when he wins the rebellious Gene as a friend in his last year of high school. Gene is adored by many girls and manages to teach Jonathan a few lessons. Gene himself would rather just be with one girl: his girlfriend Bunny. But since his father is poor, her parents don't accept him.
Eighties teenager Marty McFly is accidentally sent back in time to 1955, inadvertently disrupting his parents' first meeting and attracting his mother's romantic interest. Marty must repair the damage to history by rekindling his parents' romance and - with the help of his eccentric inventor friend Doc Brown - return to 1985.