Utter darkness prevailed there, but momentarily flicking the light of a pocket-lamp upon the floor before me, I discovered the further steps that were to be negotiated, and descended into the square yard which gave access to the path skirting the creek. The moonlight drew a sharp line of shadow along the wall of the house above me, but the yard itself was a well of darkness. I stumbled under the rotting brick archway, and stepped gingerly upon the muddy path that I must follow. One hand pressed to the damp wall, I worked my way cautiously along, for a false step had precipitated me into the foul water of the creek. In this fashion and still enveloped by dense shadows, I reached the angle of the building. Then--at risk of being perceived, for the wharf and the river both were bathed in moonlight-- I peered along to the left.... Out onto the paved pathway communicating with the wharf came Smith, shepherding his tottering charge. I was too far away to hear any conversation that might take place between the two, but, unless Smith gave the pre-arranged signal, I must approach no closer. Thus, as one sees a drama upon the screen, I saw what now occurred--occurred with dramatic, lightning swiftness. Releasing Smith's arm, the old woman suddenly stepped back ... at the instant that another figure, a repellent figure which approached, stooping, apish, with a sort of loping gait, crossed from some spot invisible to me, and sprang like a wild animal upon Smith's back! It was a Chinaman, wearing a short loose garment of the smock pattern, and having his head bare, so that I could see his pigtail coiled upon his yellow crown. That he carried a cord, I perceived in the instant of his spring, and that he had whipped it about Smith's throat with unerring dexterity was evidenced by the one, short, strangled cry that came from my friend's lips. Then Smith was down, prone upon the crazy planking, with the ape-like figure of the Chinaman perched between his shoulders--bending forward-- the wicked yellow fingers at work, tightening--tightening--tightening the strangling-cord! Uttering a loud cry of horror, I went racing along the gangway which projected actually over the moving Thames waters, and gained the wharf. But, swift as I had been, another had been swifter! A tall figure (despite the brilliant moon, I doubted the evidence of my sight), wearing a tweed overcoat and a soft felt hat with the brim turned down, sprang up, from nowhere as it seemed, swooped upon the horrible figure squatting, simianesque, between Smith's shoulder-blades, and grasped him by the neck. I pulled up shortly, one foot set upon the wharf. The new-comer was the double of Nayland Smith! Seemingly exerting no effort whatever, he lifted the strangler in that remorseless grasp, so that the Chinaman's hands, after one quick convulsive upward movement, hung limply beside him like the paws of a rat in the grip of a terrier.