 Charlie and Rhonda are a sweet and comfortable married couple on vacation with their lovely daughter Daphne. They find a rundown boarding house and its haggard owner, Joseph, an ex-con whose mother has just died and left him the house. He doesn t know why this cheerful couple would want to vacation in the worst part of Los Angeles, but he doesn t know they re vacationing from outer space, and their idea of fun is murdering lowlife out on the streets.