Night Warning is a fine psychological horror film. As the maniacally possessive aunt and guardian of a 17-year-old boy, Susan Tyrrell gives a tour-de-force performance.
Billy (Jimmy McNichol) is a basketball player at high school who has been brought up by his aunt Cheryl (Tyrrell) after his parents died in a car crash (great stunt footage) 14 years ago. An old maid, Cheryl is over-protective, opposing Billy’s desire to go to college in Denver on a hoped-for athletic scholarship to be with his girlfriend.
Cheryl maintains a candlelit memorial to an old boyfriend in the basement. The film’s horror content begins (replete with slow-motion violence and plenty of blood) when she kills a young TV repairman after failing to seduce him. Cop on the case Detective Carlson (Bo Svenson). is very closed-minded, ignoring the facts and insisting on linking the crime to a homosexual basketball coach, making Billy the prime suspect instead of his aunt.