André Masson, an auctioneer, receives a letter claiming that a common worker in Mulhouse owns a painting by Egon Schiele. André’s first reaction is to believe that it can only be fake. Despite the difficulties, he make a trip to Mulhouse anyway, the painting turns out to be a masterpiece gone missing in 1939. This could undoubtedly be the turning point of his career, but after a brief investigation, he realizes that he is handling a looted art.