André Masson, an auctioneer at the famous Scottie’s auction house, receives a letter one day stating that a painting by Egon Schiele has been discovered in Mulhouse at the home of a young worker. Very skeptical, he makes the trip and has to face the truth: the painting is authentic, a masterpiece gone missing since 1939, confiscated by the Nazis. André sees this discovery as the pinnacle of his career, but also the beginning of a struggle that could jeopardize it. Fortunately, he will be assisted by his ex-wife and colleague Bertina, and by his eccentric intern Aurore.