Tom Ricks, an American novelist in his forties, comes to Paris in the hope of re-establishing his relationship with his daughter. But nothing goes according to plan: he ends up living in a seedy hotel and is obliged to work as a night watchman. Just when he can sink no lower, Margit, a sensual, mysterious Englishwoman, suddenly appears in his life. But the rules she imposes are strict: he must never ask anything about her and can see her twice a week and no more. This strange relationship slowly develops into an intensely passionate affair.