Just before Christmas a winter blizzard sweeps across Iceland. In their remote farmhouse, Erla and Einar are hunkering down for the night - when there's a knock at the door. It's a stranger, desperate for shelter.
They take him in - but they'll wish they hadn't. Because this man is not who he says he is. And, when the power cuts out, it's the beginning of a terrifying ordeal .
. . Later, Detective Hulda Hermannsdottir - recovering from a family tragedy - is called to an isolated farmhouse.
Bodies await her and a haunting mystery . . .