In the suburbs of Rockton, an uninvited guest has crashed the party. Anthony Ulrich, known as The White Hall Slayer, is on the loose. Having recently escaped from Willows Grove Institution, he cuts a deadly path of slaughter that leads him to a sleepover.

On his trail is Gregory Quinton, a detective who is battling the memories of his past while seeking out the lunatic who is responsible for a climbing death toll. One he fears will continue to increase as the night goes on.

Lock your doors. Turn out the lights. Hug your children. Nobody is safe in The Sleepover Massacre.