Dimwitted Martians misunderstands that they are about to invade the Earth. Thinking they are late, they rush in with their ramshackle spaceship and land in Big Bean, Illinois, a peaceful midwestern town. Annoucing that they want to kill the "Earth scum", they are tracked down by the residents. Luckily, the town sheriff and his daughter help to keep them safe and find the way to return them safety to the space.