An aging horror star and a psychotic veteran come face to face at the premiere of the star's most recent film.

After a screening of his latest film, famous horror film star Byron Orlok announces his retirement. Despite the anger of his producer and the pleas of director-writer Sammy Michaels, Orlok is adamant. As he leaves for his limousine, he is momentarily caught in the cross-hair of a telescopic-sight rifle being tested in a gunshop across the street by young Bobby Thompson. After adding the rifle to an arsenal of weapons in his car trunk, Thompson drives to his San Fernando Valley home, where he lives with his wife, Ilene, and his parents. That evening, as Ilene prepares to leave for her night job, Thompson asks her to stay home, but she refuses. When she greets him the next morning, Thompson shoots her and then kills his mother and a delivery boy in the kitchen. After leaving behind a note stating that there will be more killing before he dies, Thompson drives to a complex of gasoline tanks overlooking a freeway, climbs atop one of the tanks, eats his lunch, and begins shooting people in the passing cars. When the police arrive, he escapes to a drive-in theater where Byron Orlok is scheduled to make a personal appearance. The previous evening, Orlok had refused to go to the drive-in and, following an argument with his secretary, remained in his hotel suite. After drinking half a bottle of Scotch, he was visited by the drunken Sammy Michaels; they talked but resolved nothing and passed out on the bed. The next day, however, Orlok agreed to appear at the drive-in. By the time Orlok and his party arrive, Thompson has poked a hole in the screen and begun firing at people in their cars. As panic breaks out, Orlok decides to confront the killer; upon seeing the real Orlok approaching (appearing simultaneously on the screen), Thompson becomes so confused that he is easily taken by the police.