The clock struck midnight as the mansion's grand hall echoed with the sound of a distant, haunting melody playing softly. Detective Harper arrived at the scene, his trench coat flapping in the cold wind, eyes scanning for any suspicious activity nearby. A scream pierced the silence, sending shivers down the spines of the guests who had gathered for the lavish party. Lady Evelyn, the hostess, clutched her pearls tightly, her face pale as she pointed towards the darkened library door. The butler, Mr. Graves, hurried to her side, his expression grim as he whispered something urgently into her ear. Detective Harper approached cautiously, his flashlight revealing a trail of blood leading from the library to the grand staircase. The guests murmured in fear, their whispers blending into a cacophony of dread as they awaited the detective's next move. Harper knelt beside the blood trail, examining it closely, his mind racing with possibilities and motives for the gruesome act. Lady Evelyn's eyes filled with tears as she recounted the events leading up to the discovery of the chilling scene. The detective stood, determination etched on his face, ready to uncover the secrets hidden within the mansion's shadowy corridors.