Galaxy Quest (1999) | Spaceballs (1987)

Galaxy Quest

The stars of a 1970s sci-fi show - now scraping a living through re-runs and sci-fi conventions - are beamed aboard an alien spacecraft. Believing the cast's heroic on-screen dramas are historical documents of real-life adventures, the band of aliens turn to the ailing celebrities for help in their quest to overcome the oppressive regime in their solar system.

Spaceballs

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).