In a distant galaxy, planet Spaceball has depleted its air supply, leaving its citizens reliant on a product called "Perri-Air." In desperation, Spaceball's leader President Skroob (Mel Brooks) orders the evil Dark Helmet (Rick Moranis) to kidnap Princess Vespa (Daphne Zuniga) of oxygen-rich Druidia and hold her hostage in exchange for air. But help arrives for the Princess in the form of renegade space pilot Lone Starr (Bill Pullman) and his half-man, half-dog partner, Barf (John Candy).