New York: Every night the mysterious "Night Owl" goes on the air with her moody radio show. She seems to have an inexplicable influence on some men; several of Julie's friends commit suicide while listening to her voice. She fears for her husband Harry, who becomes more and more distant from her.

After a 17-year-old shoots his parents dead and then turns the gun on himself, an investigative reporter makes a disturbing discovery. The adopted boy was born to a mother who, as a teen, inexplicably murdered her parents as well. Even more alarming is the discovery that the dead boy has a twin, who may also be genetically predisposed to kill.

A deranged man hides in the attic of a new house and becomes obsessed with the unsuspecting family that moves in.