An on-the-run twisted family of circus performers live in the remote Scottish highlands, miles away from civilisation. When a team of Roller Derby girls go camping just a bit too close to them all hell breaks loose.

Sophie's 18th birthday becomes a bloodbath when monsters descend upon her house, devouring the guests and killing anyone who tries to leave. To survive the night, Sophie must face her destiny: monsters are real and she's the only one who can stop them.