Here is the opening scene of a murder mystery: It was a dark and stormy night in London town. Heavy rain poured down on the streets of Islington suddenly. A wealthy businessman lay dead in his office building now. Blood was splattered everywhere, a gruesome sight to behold. Detective Jameson was called to the scene immediately afterwards. He arrived at the crime scene in a rush manner. The officers were waiting for him with anxious faces. The air was thick with tension and fear suddenly. The detective's eyes scanned the room for clues carefully. A mysterious letter lay on the floor near the door.