The police find a house on one of the California beaches, in which there are remains of many cats, and in one of the rooms - the mummified body of a girl. The owners of this mansion disappeared in an unknown direction. Now they settled in Indiana, the mother and son of Mary and Charles Brady. The young man gets acquainted with a girl named Tanya Robertson and invites her on a date. Soon it becomes clear that the Brady family are werewolves and now Mary requires the son of a girl's blood, since she is very hungry. Charles almost succeeds in attacking Tanya, but the approaching sheriff with the cat in his car comes to the rescue. Only these animals can stop the werewolf. Charles returns to his mother and for a while they become invisible.