A year after her sister Melanie’s mysterious disappearance, Clover and her friends travel to the remote valley where she vanished in search of answers. While exploring an abandoned visitor center, they are stalked by a masked killer and horribly murdered one by one. Trapped in the valley, they are forced to relive the nightmare over and over again – only each time the murderous threat changes, each more terrifying than the last. With hope fading, the group soon realizes that they have a finite number of deaths left and the only way to escape is to survive until dawn.