In the heart of London, fog rolled in, casting eerie shadows. The clock tower chimed midnight, its echo haunting the deserted streets. A cab pulled up outside a grand, abandoned mansion. A mysterious figure stepped out, cloaked in black. They knocked, the knocker echoing through the eerie silence. No response. The figure slipped a key from their pocket, unlocking the heavy oak door. Inside, darkness lurked, heavy curtains blocking out the moon. The figure struck a match, revealing a dimly lit staircase. They ascended, each step creaking ominously. At the top, a door stood ajar. A sudden gust blew it open, revealing a dimly lit room. In the center, a body lay lifeless, a single gunshot wound to the head. The figure froze, their breath visible in the cold air. The room was silent, save for the ticking of a distant clock.