Scream for Help (1984)
First he tried to kill mom. Now he's after me. But no one believes me!
Rachael Kelly stars in Scream for Help as the happy-go-lucky, 17-year-old girl with an overbearing sense of curiosity. When she learns that her stepfather, Paul Fox, is cheating on her mother, Kelly, she begins to spy on him. She eventually uncovering his dubious plan to murder her mom. When she tries to tell the authorities, they scoff at her accusations.