Run: 2026-02-16-01KHM5Q69XA0SMPQB8RQQ78HRY

Detective Arlo Finch studied the impossible crime scene. The library doors had been locked from the inside. A single dagger protruded from the victim's motionless chest. Yet there was no trace of the murderer's presence. Lord Blackwood sat perfectly still in his leather armchair. His empty eyes reflected the fire's dying, desperate glow. No windows were broken; the chimney was far too narrow. The floor showed no footprints besides their own. Every book remained upon its shelf, neat and orderly. The only disturbance was a fallen chess piece. A black queen rested near the victim's right shoe. This was, without any doubt, a perfect locked room. Finch carefully picked up the queen with gloved fingers. He detected a faint, unfamiliar scent of bitter almonds. "Poison, as well," he murmured to his silent partner. The puzzle now had two distinct, contradictory methods. Someone had executed an utterly flawless, theatrical murder. But every perfect crime must contain a single flaw. Detective Finch began his search for that tiny error.