She was a captive; of that there could be no doubt, a captive in the hands of the giant criminal whose wiles were endless, whose resources were boundless, whose intense cunning had enabled him, for years, to weave his nefarious plots in the very heart of civilization, and remain immune.  Suddenly—­

“That woman is a sorceress!” muttered Nayland Smith.  “There is about her something serpentine, at once repelling and fascinating.  It would be of interest, Petrie, to learn what State secrets have been filched from the brains of habitues of this den, and interesting to know from what unsuspected spy-hole Fu-Manchu views his nightly catch.  If ...”

His voice died away, in a most curious fashion.  I have since thought that here was a case of true telepathy.  For, as Smith spoke of Fu-Manchu’s spy-hole, the idea leapt instantly to my mind that this was it—­this strange platform upon which we stood!

I drew back from the rail, turned, stared at Smith.  I read in his face that our suspicions were identical.  Then—­

“Look!  Look!” whispered Weymouth.

He was gazing at the trapdoor—­which was slowly rising; inch by inch ... inch by inch ...  Fascinatedly, raptly, we all gazed.  A head appeared in the opening—­and some vague, reflected light revealed two long, narrow, slightly oblique eyes watching us.  They were brilliantly green.

“By God!” came in a mighty roar from Weymouth.  “It’s Dr. Fu-Manchu!”

As one man we leapt for the trap.  It dropped, with a resounding bang—­ and I distinctly heard a bolt shot home.

A gutteral voice—­the unmistakable, unforgettable voice of Fu-Manchu—­ sounded dimly from below.  I turned and sprang back to the rail of the platform, peering down into the hashish house.  The occupants of the divans were making for the curtained doorway.  Some, who seemed to be in a state of stupor, were being assisted by the others and by the man, Ismail, who had now appeared upon the scene.

Of Karamaneh, Zarmi, or Fu-Manchu there was no sign.

Suddenly, the lights were extinguished.

“This is maddening!” cried Nayland Smith—­“maddening!  No doubt they have some other exit, some hiding-place—­and they are slipping through our hands!”

Inspector Weymouth blew a shrill blast upon his whistle, and Smith, running to the rail of the platform, began to shatter the panes of the skylight with his foot.

“That’s hopeless, sir!” cried Weymouth.  “You’d be torn to pieces on the jagged glass.”

Smith desisted, with a savage exclamation, and stood beating his right fist into the palm of his left hand, and glaring madly at the Scotland Yard man.

“I know I’m to blame,” admitted Weymouth; “but the words were out before I knew I’d spoken.  Ah!”—­as an answering whistle came from somewhere in the street below.  “But will they ever find us?”

He blew again shrilly.  Several whistles replied ... and a wisp of smoke floated up from the shattered pane of the skylight.