Back to the Future Part III (or Back to the Future III) is the title of a video game based on the film of the same name.The game is different from LJN’s Back to the Future Part II & III video game released for the NES.The game was released in 1991 for the Sega Genesis, Amiga, Amstrad CPC, Atari ST, Commodore 64, MS-DOS, Sega Master System, and the ZX Spectrum.

https://en.wikipedia.org/wiki/Back_to_the_Future_Part_III_(video_game)