A young city couple, Ed and Sarah, decide to start afresh by relocating from London to a secluded farmhouse on the Scottish borders. Enchanted by the charm of the 19th-century Castle Farm and its potential for renovation, they are eager to begin their project. On their first night, Sarah hears strange noises in the dark, but Ed dismisses them as mere figments of her imagination. Unsettled by the feeling that they are not alone, Sarah insists that Ed check it out. When he fails to return after an unnervingly long time, she ventures downstairs, only to be met by a group of masked intruders. As she frantically searches for Ed, a chilling game of cat and mouse unfolds with the enigmatic attackers. But what are their intentions, and what sinister plans do they have for the new arrivals?