My brain reeled, and a weakness, mental and physical, threatened to conquer me completely.  Indeed, I think I must have succumbed, sapped as my strength had been by the drug administered to me, if the sound of a creaking stair had not arrested my attention and by the menace which it conveyed afforded a new stimulus.

Some one was creeping down from the landing above—­coming to my room!  The creatures of the Yellow doctor, having despatched Nayland Smith, were approaching stealthily, stair by stair, to deal with me!

From my grip I took out the Browning pistol.  The Chinese doctor’s servants should have a warm reception.  I burned to avenge my friend, who I was persuaded, lay murdered in the room above.  I partially closed the door and took up a post immediately behind it.  Nearer came the stealthy footsteps—­nearer....  Now the one who approached had turned the angle of the passage....

Within sight of my door he seemed to stop; a shaft of white light crept through the opening, across the floor and on to the wall beyond.  A moment it remained so—­then was gone.  The room became plunged in darkness.

Gripping the Browning with nervous fingers I waited, listening intently; but the silence remained unbroken.  My gaze set upon the spot where the head of this midnight visitant might be expected to appear, I almost held my breath during the ensuing moments of frightful suspense.

The door was opening; slowly—­slowly—­by almost imperceptible degrees.  I held the pistol pointed rigidly before me and my gaze remained fixed intently on the dimly seen opening.  I suppose I acted as ninety-nine men out of a hundred would have done in like case.  Nothing appeared.

Then a voice—­a voice that seemed to come from somewhere under the floor snapped:—­

“Good God! it’s Petrie!”

I dropped my gaze instantly ... and there, looking up at me from the floor at my feet, I vaguely discerned the outline of a human head!

“Smith!” I whispered.

Nayland Smith—­for indeed it was none other—­stood up and entered the room.

“Thank God you are safe, old man,” he said.  “But in waiting for one who is stealthily entering a room, don’t, as you love me, take it for granted that he will enter upright.  I could have shot you from the floor with ease!  But, mercifully, even in the darkness, I recognized your Arab slippers!”

“Smith,” I said, my heart beating wildly, “I thought you were drugged—­ murdered.  The port contained an opiate.”

“I guessed as much!” snapped Smith.  “But despite the excellent tuition of Dr. Fu-Manchu, I am still childishly trustful; and the fact that I did not partake of the crusted ’45 was not due to any suspicions which I entertained at that time.”

“But, Smith, I saw you drink some port.”

“I regret to contradict you, Petrie, but you must be aware that the state of my liver—­due to a long residence in Burma—­does not permit me to indulge in the luxury of port.  My share of the ’45 now reposes amid the moss in the tulip-bowl, which you may remember decorated the dining table!  Not desiring to appear churlish, by means of a simple feat of legerdemain I drank your health and future happiness in claret!