The grandfather clock chimed midnight as Detective Sarah Chen stepped through the ornate doorway into the sprawling Victorian mansion's dimly lit foyer. Rain drummed against tall windows while thunder rumbled overhead, casting eerie shadows across the polished marble floors of the grand estate's entrance. Mrs. Blackwood's lifeless body lay crumpled at the bottom of the curved staircase, her emerald necklace glinting under the flickering chandelier's pale light. Blood pooled beneath her silver hair as the butler stood frozen nearby, his white gloves trembling and his face drained of color. The detective's trained eyes immediately noticed the broken banister rail above and the scattered rose petals leading down from the second floor landing. Three potential suspects waited nervously in the drawing room: the victim's nephew, her personal secretary, and the mysterious late-night visitor from London. Chen pulled out her notebook and began documenting the scene, knowing that someone in this house had committed the perfect crime.