American writer Tom Ricks (Ethan Hawke) comes to Paris desperate to put his life together again and win back the love of his estranged wife and daughter. When things don't go according to plan, he ends up in a shady hotel in the suburbs, having to work as a night guard to make ends meet. Then Margit (Dame Kristin Scott Thomas), a beautiful, mysterious stranger walks into his life and things start looking up. Their passionate and intense relationship triggers a string of inexplicable events, as if an obscure power was taking control of his life.
A college lecturer flees to Paris after a scandal costs him his job. In the City of Light, he meets a widow who might be involved in a series of murders.