I departed, my wonder growing. All this rigmarole evidently had a meaning, but one which I could not fathom. Back in the opium room Hassim bade me be seated on some cushions to await his return. To my question he snarled that he was going forth as he had been ordered, to buy me a ticket on the Channel boat. He departed and I sat down, leaning my back against the wall. As I ruminated, it seemed suddenly that eyes were fixed on me so intensely as to disturb my sub-mind. I glanced up quickly but no one seemed to be looking at me. The smoke drifted through the hot atmosphere as usual; Yussef Ali and the Chinese glided back and forth tending to the wants of the sleepers.
Suddenly the door to the rear room opened and a strange and hideous figure came haltingly out. Not all of those who found entrance to Yun Shatu's back room were aristocrats and society members. This was one of the exceptions, and one whom I remembered as having often entered and emerged therefrom. A tall, gaunt figure, shapeless in ragged wrappings and nondescript garments, face entirely hidden. Better that the face be hidden, I thought, for without doubt the wrapping concealed a grisly sight. The man was a leper, who had somehow managed to escape the attention of the public guardians and who was occasionally seen haunting the lower and more mysterious regions of East End—a mystery even to the lowest denizens of Limehouse.
Suddenly my supersensitive mind was aware of a swift tension in the air. The leper hobbled out the door, closed it behind him. My eyes instinctively sought the couch whereon lay the man who had aroused my suspicions earlier in the day. I could have sworn that cold steely eyes gleamed menacingly before they flickered shut. I crossed to the couch in one stride and bent over the prostrate man. Something about his face seemed unnatural—a healthy bronze seemed to underlie the pallor of complexion.
"Yun Shatu!" I shouted. "A spy is in the house!"
Things happened then with bewildering speed. The man on the couch with one tigerish movement leaped erect and a revolver gleamed in his hand. One sinewy arm flung me aside as I sought to grapple with him and a sharp decisive voice sounded over the babble which broke forth:
"You there! Halt! Halt!"
The pistol in the stranger's hand was leveled at the leper, who was making for the door in long strides!
All about was confusion; Yun Shatu was shrieking volubly in Chinese and the four China boys and Yussef Ali were rushing in from all sides, knives glittering in their hands.
All this I saw with unnatural clearness even as I marked the stranger's face. As the flying leper gave no evidence of halting, I saw the eyes harden to steely points of determination, sighting along the pistol barrel—the features set with the grim purpose of the slayer. The leper was almost to the outer door, but death would strike him down ere he could reach it.
And then, just as the finger of the stranger tightened on the trigger, I hurled myself forward and my right fist crashed against his chin. He went down as though struck by a trip-hammer, the revolver exploding harmlessly in the air.