Dr. Brown (Christopher Lloyd) always has some weird inventions. During an experiment with the time machine he invented, he found Martin (Michael J. Fox), a high school student who had never known each other for a long time. Unexpectedly, the doctor was killed by the gangsters during the experiment. Martin fled with the time machine in a panic and returned to 30 years ago. Martin met his father George (Crispin Glover) and mother Lorraine (Lea Thompson) 30 years ago. Martin was looking for Dr. Brown 30 years ago so that he could go back to the future, and tried his best to match George and Lorraine so that he would not disappear in the future. But George was cowardly, and Martin made a fool of himself in the process of matching and made Lorraine fall in love with him. There was also the annoying Bev who got in the way, which made Martin very angry. Martin was dealing with his parents, and he had to find the doctor as soon as possible to find a way to go back to the future...