Barbra and her brother Johnny travel by car from Pittsburgh to the countryside to visit the gravestone of their father in the cemetery. Out of the blue, they are attacked by a strange man and Johnny is murdered. Barbra runs and releases the brake of Johnny's car since the keys are in his pocket, and flees to an isolated farmhouse, where she locks herself inside. Barbra is in shock and soon she finds a man, Ben, who is also escaping from the inhuman creatures and he reinforces the doors, windows and openings in the house. He also finds a shotgun and a radio and they learn that the radiation from a satellite that was returning from Venus has somehow reactivated the brain of the dead. Then they find five humans hidden in the basement: Harry Cooper, his wife Helen and their daughter Karen that is sick; and Tom and his girlfriend Judy. Harry has an argument with Ben, since he believes that the basement is the safest place for them and Harry goes not agree.