Night Warning
Tags: cult, murder, violence

Plot synopsis:
Billy Lynch (Jimmy McNichol) is a high school student whose parents died in a car accident and has been raised by his aunt, Cheryl (Susan Tyrrell), who is overly protective of him. A gifted basketball player, Billy is offered a chance at a scholarship to attend the University of Colorado, but Cheryl dismisses the idea, assuming that Billy will stay with her to "contribute." At school, Billy is bullied by one of his basketball teammates, Eddie (Bill Paxton), who is jealous of Billy's close friendship with their coach, Tom Landers (Steve Eastin), while Julia (Julia Duffy), the school's journalism photographer, begins to take romantic interest in Billy.
On Billy's seventeenth birthday, Cheryl changes her mind about the scholarship, and asks Billy to stop by the television repair shop to have the technician, Phil Brody, come by to look at their set. That night, after Phil works on their television, Cheryl makes aggressive sexual advances toward him; when he refuses, Cheryl stabs him to death with a kitchen knife. Billy and Cheryl's neighbor friend, Margie arrive immediately after the ordeal, and Cheryl claims Phil attempted to rape her.
A bigoted police detective, Joe Carlson (Bo Svenson) is assigned to the case, and is skeptical of Cheryl and the alleged rape. After discovering that Phil Brody was homosexual, and that he was in a same-sex relationship with Billy's coach, Tom Landers, he incorrectly assumes the murder to be a result of a love triangle between the three men.
Det. Carlson begins regularly questioning Billy, accusing him of being a "fag", and harasses Coach Landers, forcing him to resign from the high school for being gay. Det. Carlson also inquires from Julia about her and Billy's sexual relationship. Meanwhile, Cheryl drugs Billy's milk which causes him to perform poorly at his scholarship tryout, and cleans out the attic so he can have an apartment space in the house. Sergeant Cook (Britt Leach), who has been casing Cheryl's home, believes Billy to be innocent, and is suspicious of Cheryl.
After walking in on Billy and Julia having sex, Cheryl becomes increasingly enraged with Billy. In the attic, Billy finds a photo of a man named Craig, whom Cheryl claims was one of his mother's old boyfriends. Billy asks Julia to come by the house to distract Cheryl so that Billy can investigate further; locked in a box upstairs, he finds his birth certificate, indicating that Cheryl is actually his mother, and that Craig was his father. Meanwhile, downstairs, Cheryl strikes Julia in the head with a meat tenderizer in a fit of jealousy, and again drugs Billy with milk, knocking him unconscious.
Julia awakens in a secret room in the basement, where she discovers Craig's mummified corpse and his severed head in a jar of formaldehyde, next to a makeshift shrine. Cheryl's suspicious neighbor, Margie, arrives shortly after to investigate the goings-on on the property, and is followed into the woods behind the house by Cheryl, who stabs her to death with a machete. Sergeant Cook then enters the house in search of Julia, who has been reported missing by her mother, and is also murdered by Cheryl after discovering Julia in the basement. Cheryl chases Julia out of the house, and they both fall in a pond near the forest, where Cheryl again knocks Julia unconscious.
Billy awakens in the attic, which Cheryl has adorned with his childhood toys, and stumbles downstairs to call the police. While attempting to dial 911, Cheryl attacks him with a knife, and a violent struggle ensues, ending with Billy impaling her with a fireplace poker. Billy calls Coach Landers, asking for help. Shortly after, Det. Carlson arrives at the house, where he finds Coach Landers treating Billy's stab wounds, and sees Cheryl's lifeless body on the floor.
In a rage, Det. Carlson blames Billy and Tom for the crimes, and draws his gun on them, despite Julia's insistent cries that Cheryl was responsible. Coach Landers and Det. Carlson get into a scuffle, during which Billy is able to grab the gun, shooting Carlson multiple times. Carlson bleeds to death in front of the living room piano while Billy and Julia embrace, both crying.