A young woman is hit in the middle of the night by the utility van of a forest ranger. She was running breathlessly in the middle of the forest, half-naked and covered in blood. Blood that isn’t her own – Hyppolite identifies the probable location from which the young woman was fleeing: a long-abandoned manor house. When Chloe and Rocher visit it, they understand the residence probably hosted some very special parties under the direction of the Marquis de Sade. Evidence seems to show that the last of these parties degenerated into murder.