There was a crash as Holmes's

square had opened in the planks. Killer Evans struck a match, lit a stump of candle, and vanished from our view.

Clearly our moment had come. Holmes touched my wrist as a signal, and together we stole across to the open trapdoor. Gently as we moved, however, the old floor must have creaked under our feet, for the head of our American, peering anxiously round, emerged suddenly from the open space. His face turned upon us with a glare of baffled rage, which gradually