Target Earth: A large city is ordered to be completely evacuated as an army of robots, believed to be from the planet Venus, attack it. Left behind are Nora King and Frank Brooks, strangers until their chance meeting in the deserted streets. They meet a celebrating couple at a café, Vicki Harris and Jim Wilson. The quartet escape the robot patrol and take refuge in a large hotel. There, they encounter a new danger in Davis, a psychopathic killer. Venus robots or not, Davis practices his profession.