Ralph and Sylvia Nebula and their friend Mavis Goldfarb are bitter at being sent to a bogus weight-loss camp, so they decide to escape and find a way to take revenge on those responsible for promoting the idea that thin is better.
After Ralph and Sylvia Nebula flee a fat camp ashram to join their friend Mavis at a dude ranch, they help her unite the Western town's factions by preparing for the arrival of an unidentified flying object.