The story focuses on a group of teenagers who decide to stay behind in their school on Halloween to perform a summoning ritual using an Ouija board. They unwittingly conjure an unknown force that hunts them one by one, torturing and killing them graphically. Only the film student Sam, who documented the ritual, survives as the "final girl" in keeping with horror movie conventions. The teenagers' reckless behavior and moral sins are punished by their horrific deaths at the hands of the supernatural entity they have unleashed within the abandoned school grounds.