The eighteenth mystery in the New York Times bestselling Parisian detective series! A dying man drags his oxygen machine into the office of Éric Besson, a Parisian lawyer. The old man is carrying a dilapidated notebook full of meticulous investment records. For decades, he's been helping a cadre of dirty cops launder stolen money. The notebook contains his full confession. He is adamant that Besson get the notebook into the hands of La Proc, Paris's chief prosecuting attorney, so the corruption can finally be brought to light. But en route, Besson's courier is murdered, and the notebook disappears.