The L. X. Clew (1917)

Smith, a butler in the home of Nelson, has his shoes mended, and the cobbler marked "L. X." in Roman numerals on the soles of the shoes. The butler is a smooth crook, and plans to steal Mrs. Nelson's diamond necklace, does so, makes it appear as if some one on the outside had performed the robbery. Detectives summoned discover a faint chalk mark on the window "L. X." Later they discover the marking "L. X." on the butler's shoe. This leads to a search of the butler's room, where evidences of guilt are discovered. Detective King remarks that the butler's watch has stopped. He opened the timepiece to find the works removed and the necklace hidden in the case.