The mansion stood completely silent. Lady Pemberton lay sprawled dead. Blood pooled beneath her body. The grandfather clock struck midnight. No servants remained on duty. Every window was locked tight. The study door hung open. Papers scattered across the floor. A letter opener gleamed red. Detective Shaw arrived within minutes. Rain pounded against the windows. He surveyed the ghastly scene. "Nobody leaves this house tonight." The butler trembled near the doorway. Three guests huddled together nervously. Someone here was a killer. The storm grew even stronger. Lightning illuminated their pale faces. Detective Shaw began his investigation. This would be a long night.