An improvisational comedian, working with The Committee improv group in San Francisco, struggles to be taken seriously.

The film features a conversation between Lucas and Francis Ford Coppola, producer of THX 1138. They discuss Lucas' vision for the film, including his ideas about science fiction in general and in particular his concept of the "used future" which would famously feature in his film Star Wars. Intercut with this discussion is footage shot prior to the start of production of THX 1138 showing several of its actors having their heads shaved, a requirement for appearing in the film. In several cases the actors are shown being shaved in a public location. For example, Maggie McOmie is shaved outside the Palace of Fine Arts in San Francisco, while Robert Duvall watches a sporting event as his hair is cut off. Another actor, Marshall Efron, who would later play an insane man in the film, cut off his own hair and was filmed doing so in a bathtub.

In 1995, Italy annihilates Libya, which destroys Israel. Africa bombs Germany, which in turn attacks France. Luxembourg conquers England. Sweden, Monte Carlo and Switzerland immolate themselves.The Russians decide to liquidate the Americans, who unleash their nuclear fleet, leaving only two continents on the verge of World War IV.

In the world of the Murkworks where nightmares are made, the evil Synonamess Botch hatches a scheme to make non-stop nightmares. Only Ralph and Mumford, misfits from the cheery land of Frivoli where good dreams are made, can stop him.

Five pastel-colored talking (Fluppy) dogs who arrive through a Fluppy interdimensional doorway. Upon arrival, the dogs befriend 10-year-old Jamie and his neighbor Claire. The friends must help the Fluppy dogs avoid the clutches of the evil exotic-animal collector Wagstaff and find the doorway that will lead them back to their world.

Doc Holliday travels to Tombstone, Ariz., with prostitute Katie Elder. Although the trip is difficult because Doc is ill with tuberculosis, they eventually reach their destination, where Holliday is reunited with his old friend Marshal Wyatt Earp, who has been clashing with the Clanton gang. Tensions between Earp and the Clantons rise until their infamous final showdown brings it to a head.

Rodney Copperbottom is a young robot inventor who dreams of making the world a better place, until the evil Ratchet takes over Big Weld Industries. Now, Rodney's dreams – and those of his friends – are in danger of becoming obsolete.