Nightmare

George Tatum is incarcerated in a New York City psychiatric institution for years after sexually mutilating and murdering a family in Brooklyn. Diagnosed with schizophrenia, amnesia, and epilepsy, he undergoes an experimental procedure that 'reprograms' his brain, supposedly reforming him into an upstanding citizen.

Following the procedure, George is released and visits a Times Square peep show, triggering hazy flashbacks of his father's murder. The encounter unsettles him as memories of past violence resurface.

George obtains a car and drives south toward his ex-wife Susan Temper's Florida home, seeking to reconnect with his family. This road trip marks a break from rehabilitation and sets the stage for new acts of violence.

En route, his car breaks down in Myrtle Beach, South Carolina, and he is stranded overnight. The isolation leaves him with time to act on violent impulses.

While stranded, George follows a woman home from a local bar and brutally slashes her to death. The killing demonstrates that he remains dangerous and capable of murderous acts despite his earlier reconditioning.

Back in New York, George's psychiatrists discover he has fled the city and begin tracking his movements. They mobilize to monitor his route and anticipate his next target.

In Florida, Susan's house begins receiving numerous disturbing phone calls that go unanswered by the family. Unbeknownst to them, George is the caller.

C.J. begins insisting that a strange man—his father George—is following him, but Susan dismisses it as another prank. The family remains unaware of the danger closing in.

George murders Tony, a classmate of C.J., and Candy, a teenage girl, in an abandoned house during a game of hide-and-seek. These killings intensify the danger looming over the Florida family.

Kathy agrees to babysit the children the following day while Susan attends a party. During the night, George infiltrates the house and murders Kathy and her boyfriend with a rock pick.

After donning one of C.J.'s Halloween masks, an old man George pursues the children, who barricade themselves in the upstairs bedrooms. The tense pursuit heightens the fear and danger in the home.

C.J. obtains a revolver from his mother's dresser and shoots George eight times, ending the immediate threat. The child emerges as the unlikely savior in a moment of brutal violence.

In his dying moments, George has a full recollection of his childhood, including witnessing his father engaging in sadomasochistic sex with another woman and murdering them with a felling axe. The memory reveals the source of his own violent urges.

Susan returns home to find police removing George's body and hysterically identifies him as her husband. The film ends with C.J. sitting in a police car, winking knowingly at the camera.