The game follows the plot of the movies, the player controlling Marty as he travels to 2015 to prevent his future son from committing a crime, and then traveling back in time to try to correct Biff's nefarious deeds which altered the future significantly. Once part II ends, Marty becomes stranded in 1955 and receives a letter from the Doc from 1885 asking to be rescued. Much of this plot also focuses on Marty finding and returning items to their rightful locations.