Newly-trained child psychologist Mina has little experience. In a field full of experts, she's been unable to find work, instead aimlessly spending her days stuck in the stifling heat wave sweeping across Britain. So it feels like a welcome reprieve when journalist Sam Hunter approaches her with a proposition. Alice Webber is a thirteen-year-old girl who claims she's being haunted by a witch. Living with her family in the remote Cornish village of Banathel, Alice's symptoms are increasingly disturbing. Taking this job will give Mina some experience; Sam will get the scoop of a lifetime; and Alice will get better, Mina is sure of it. But as Alice's behaviour becomes increasingly inexplicable and intense, the dark cracks in Banathel begin to show. The village has a deep history of superstition and witchcraft. They believe there is evil in the world, and they have ways of dealing with it.