People in the future live in a totalitarian society. A technician named THX 1138 lives a mundane life between work and taking a controlled consumption of drugs that the government uses to make puppets out of people. As THX is without drugs for the first time he has feelings for a woman and they start a secret relationship.

Perennially stoned Cheech and Chong tear through the city of Los Angeles, causing trouble wherever they go. After Cheech loses his job, the two pot enthusiasts head to the welfare offices where Cheech's girlfriend, Donna, works. Instead of collecting unemployment, they find themselves thrown back on the streets, searching for a way to earn new income. But when Cheech's cousin, "Red" Mendoza, arrives, things get even crazier.

Coy "Cannonball" Buckman and his blazing red Pontiac enter the Trans-America Grand Prix, an underground road race spanning the continent in which there are no rules, no speed limits and no heed for the law. En route, Buckman jockeys with an international ensemble of racers for a $100,000 purse. But there are none more important than Cade Redman, his direct competition for a guaranteed spot on the elite Modern Motors racing team.

A small town with a population of 52 people has balls galore, as in bowling balls, which they use to form a zany bowling tournament to save the town.

A group of misfits who want to find a happier life somewhere out of society decide to leave town on a PBY flying boat. The problem is that their transport needs a lot of work before they can fly it.