Anna has recently moved with her husband Philip to a new city, where she is left at home looking after their six-month-old baby. The new country’s language and culture are alien to her; she feels lonely and isolated. One night, while awaiting Philip's return, there is a buzz at the front door. She opens it, thinking it's him—but is confronted instead by a quartet of locals, claiming they have arrived for a housewarming party ... Has Philip not told her they were coming? Confused, Anna lets them in. And then, almost at once, more guests arrive. And a nightmare begins...