On the bleak, windswept moors of northern England, a small religious cult has cut itself off from society, believing they have found meaning in a purposeless world. Led by their prophet Nathaniel, they eagerly await the end times. But when the prophet brings in a new recruit, Stephanie, along with her rebellious daughter Judith, the group's delicate dynamic is disturbed. Judith is determined to escape, but her feelings are complicated by a growing friendship with another of the children, the naïve and trusting Moses, who has never experienced the outside world.
Meanwhile, another member is starting to have doubts of his own, unleashing a horrifying chain of events that will destroy the followers' lives.
In the aftermath, the survivors struggle to adjust to the real world, haunted by the same questions: if you've been persuaded to surrender your individual will, are you still responsible for your actions? And is there any way back?