Bobby Keller (Corey Feldman) is a slacker high school student who, while running through a short cut through a backyard in his neighborhood one night, collides with Lainie Diamond (Meredith Salenger), over whom Bobby has recently been obsessing. During the collision, elderly professor Coleman Ettinger (Jason Robards) is performing a meditation exercise in the yard with his wife Gena (Piper Laurie), theorizing that if he and his wife can enter a meditative alpha state together voluntarily, they will be able to live together forever. However, just as the Ettingers are on the verge of completing their meditation experiment, the teenagers' collision renders both teens unconscious, enacting a type of body switch between the four characters.