Vincent (Matthias Schoenaerts), a French Special Forces soldier just back from Afghanistan, is suffering from a post-traumatic stress disorder. He is hired to ensure the security of Jessie (Diane Kruger), the wife of a rich Lebanese businessman at their luxurious villa. As he starts experiencing a strange fascination for the woman he has to protect, Vincent increasingly seems to fall into paranoia. But what if he is right, and the danger is very real indeed?