Storm clouds gathered above the lonely and dark manor house. A flash of lightning briefly lit up the night sky. Inside, a rich man lay dead on the cold floor. The killer had escaped through the open French glass doors. Rain blew in and soaked the thick expensive Persian rug. Inspector Black stepped into the room from the dark hallway. He saw the body lying near the warm fireplace hearth. A golden knife was sticking out of his bare back. No one else was found in the whole empty house. This mystery would be a very difficult case to solve.