(I'm reading The Insidious Dr Fu-Manchu and have reached chapter six)
Petrie is still fairly overcome with the fumes but spots a strange figure in the back (further back; they are already in the back room behind the barber shop. How many layers deep does this go??!?) "I was able to make out a ghastly parchment face, with small, oblique eyes, and a misshapen head crowned with a coiled pigtail, surmounting a slight, hunched body. There was something unnatural, inhuman, about that masklike face, and something repulsive in the bent shape and the long, yellow hands clasped one upon the other." This in no way resembles the description of Fu-Manchu Smith has given*, but might be the hunchback from the casebook in Chapter Five. They feign opium slumber but this person is not convinced, and opens Petrie's eyelid; Petrie, knowing a little about opium (he is a doctor) rolls his eyes up to show only the white which seems to satisfy them.
Smith decides the best plan is to rush up the stairs to the upper room and after waiting for the right moment they draw their revolvers and do so. Petrie is first and meets someone:
"He wore a plain yellow robe, of a hue almost identical with that of his smooth, hairless countenance. His hands were large, long and bony, and he held them knuckles upward, and rested his pointed chin upon their thinness. He had a great, high brow, crowned with sparse, neutral-colored hair."
"Of his face, as it looked out at me over the dirty table, I despair of writing convincingly**. It was that of an archangel of evil, and it was wholly dominated by the most uncanny eyes that ever reflected a human soul, for they were narrow and long, very slightly oblique, and of a brilliant green. But their unique horror lay in a certain filminess (it made me think of the membrana nictitans in a bird) which, obscuring them as I threw wide the door, seemed to lift as I actually passed the threshold, revealing the eyes in all their brilliant iridescence."
Smith declares that it's Fu-Manchu*** and tells Petrie to shoot, but Fu-Manchu has a trapdoor and Petrie falls down it.
Petrie finds himself trapped in a dark water-filled chamber. Worse still, the room above is on fire and burning oil and other bits drop on to him. As some light comes in he realises there is no escape, although perhaps when the tide goes out he will dragged out to be found like the other bodies.
Then he notices that there is an escape; a beam that leads to an iron ladder. But as he reaches for it Smith and the hunchback appear and Smith tells him not to reach for the beam. After some difficulty they lower the (false) pigtail and fish Petrie out, but by removing the wig the hunchback is revealed to be the woman from earlier. How ironic that a beautiful woman would disguise herself as a hideous man; now there's clever for you. As he's lifted out he spots two sword blades on the beam; it was those that caused the severed fingers of the men who died.
Petrie swoons. When he wakes up the fire engines have come and Fu-Manchu is gone. Gone too is the girl; Smith explains "We shall never really excel at this business. We are far too sentimental. I knew what it meant to us, Petrie, what it meant to the world, but I hadn't the heart. I owed her your life—I had to square the account."
* Has Nayland Smith met him, observed him, or got a reliable witness account? If not how does he know what Dr Fu-Manchu looks like? Does Fu-Manchu even exist? Woah. Going to have to lie down with my pipe.
** Humble bragging a bit there Petrie; it's a little florid but the description gives us plenty to work with.
** So he has met him. Guess I got overexcited for a moment there. Better have a lie down with my pipe.