One year after her sister Melanie’s mysterious disappearance, Clover and her friends head to the remote valley where she vanished in search of answers. Exploring an abandoned visitor center, they find themselves stalked by a masked killer and horrifically murdered one by one… only to wake up to find themselves back at the beginning of the same night. Trapped in the valley, they are forced to relive the nightmare over and over again—only each time the murderous threat is different, each more terrifying than the last. With hope dwindling, the group soon realizes they have a limited number of kills left, and the only way to escape is to survive until dawn.