Madeline is married to Ernest, who was once arch-rival Helen's fiance. After recovering from a mental breakdown, Helen vows to kill Madeline and steal back Ernest. Unfortunately for everyone, the introduction of a magic potion causes things to be a great deal more complicated than a mere murder plot.

Amiable slackers Bill and Ted are once again roped into a fantastical adventure when De Nomolos, a villain from the future, sends evil robot duplicates of the two lads to terminate and replace them. The robot doubles actually succeed in killing Bill and Ted, but the two are determined to escape the afterlife, challenging the Grim Reaper to a series of games in order to return to the land of the living.

The final installment of the Back to the Future trilogy finds Marty digging the trusty DeLorean out of a mineshaft and looking for Doc in the Wild West of 1885. But when their time machine breaks down, the travelers are stranded in a land of spurs. More problems arise when Doc falls for pretty schoolteacher Clara Clayton, and Marty tangles with Buford Tannen.