It was just a patch of ice. Just a bit of bad luck. But it was nearly enough to kill Kath Redway, spinning her car into Burrator Reservoir in the beautiful Dartmoor National Park. Miraculously, Kath escapes her accident with a few bruises and amnesia. She is shocked but delighted to be back in her remote moorland farmhouse with her handsome husband Adam, and her shy, gifted daughter Lyla. She’s alive! But her family is not so delighted. Her husband is cold, even angry. Her daydreaming daughter talks ever more strangely, about a 'man on the moor'. Then, as chilling fragments of memory return, Kath realizes her 'accident' was nothing of the kind. And now her life collapses into a new world of darkness, menace, and terror.