Marty McFly (Michael J. Fox) is an ordinary teenager living in California. One day he discovers his friend Doc Brown (Christopher Lloyd) has converted a DeLorean automobile into a time machine powered by radioactive materials. Bad guys attempting to build a bomb come after Doc, so Marty must take off to save the day. Through the course of three films, he visits his teenage parents (twice), his relatives from the end of the nineteenth century, and himself in the future. Each incident slightly reshapes the "present", so not only does Marty need to protect the past, he must ensure that he ends up in a universe he actually wants to live in!