At the start of Strangers, Joanna Berrigan is home alone in her house near Munich when she is confronted by a man who is a complete stranger to her. He has let himself into the house with a key and insists he’s Erik Thieben, her fiancé, and that they live together. As he talks, attempting familiarity, nothing he says makes sense. The more he tries to comfort, the greater her terror. Furthermore, there is nothing in the house that suggests anyone else lives there. So why, the creepier he becomes, does she feel like she’s the one who’s crazy?