'Sweet 16' is Sophie Reiner - and she's a sly old dog. When her friend Karen is murdered after going to a disco, her perfect world falls apart. She falls in love with the charming detective Mike Kleist and starts a secret affair with him. When another of Sophie's classmates is murdered, the situation in the Reiner family comes to a head. Eventually, Sophie's father is targeted by the investigation. But the killer has already chosen his next victims: they are Sophie and her mother.