Everyone at Pritchett High wants an invitation to the Senior Scavenge. In 2020, Violet Warren and her friends are the lucky ones. Eight girls will break into the Poison Apple Carnival after hours for a scavenger hunt, then at sunrise they'll gather for a celebration in honor of their upcoming senior year.

But someone else has another game planned. Minutes after the girls sneak into the carnival, a madman in a rubber mask begins slashing his way through the group and Violet quickly realizes his motives are personal. As she watches her friends die in a series of increasingly bizarre attacks, she must fight to survive while trying to answer the question: What could she have done to earn a fast-pass for a roller coaster ride straight to hell?