We are in the bombed-out Berlin of 1949, after the Second World War, rendered with an atmosphere reminiscent of Orson Welles' The Third Man. Henri Robin, a special agent of the French secret service, arrives in the ruined former capital to which he feels linked by a vague but recurrent childhood memory. But the real purpose of his mission has not been revealed to him, for his superiors have decided to afford him only as much information as is indispensable...