Spaced Invaders (1990)

"For years, science has speculated on the existence of intelligent life in space... Now, there is living proof there is no such thing."

A crew of Martians overhears a radio broadcast of Orson Welles' "War of the Worlds" coming from Earth, and, thinking the Martian fleet is attacking Earth, they land their broken-down ship in a backwater mid-American town. As luck would have it, they land on Halloween and get mistaken for trick-or-treaters. Comedy ensues as the Martians try to get taken seriously.