Night Warning on AllMovie

Billy (Jimmy McNichol, Kristy's younger brother) knows something is wrong when he comes home and finds that his batty, sexually repressed Aunt Cheryl (Susan Tyrrell in a stellar performance), has ruthlessly murdered the TV repairman -- not because he was inept or overcharged, but because she was overcharged and he managed to resist her advances. A gay-bashing detective (Bo Svenson) ignores the bare facts and single-mindedly plans to pin the murder on Billy for hanging out with a sexually suspect basketball coach. Meanwhile, Aunt Cheryl is doing everything to keep her little Billy at home (she has raised him since his parents were killed in a blazing car accident when he was 14 and does not want him to leave for college), even going to the trouble of lacing his milk with sickening substances so he is not well enough to go out. She also undermines his big game when the basketball scouts will be recruiting for college teams and manages to cause the gory disappearance of most of the cast members before the final scene plays out and an interesting identity is revealed.