"On an island below the city, where the marshes begin. Once there were warehouses here, and a factory, but they were abandoned as the city grew in the other direction, and have been crumbling into ruin for twenty years. I purchased the entire island through one of my agents, and am rebuilding to suit my own purposes an old stone mansion which stood here before the factory was built. None notices, because my own henchmen are the workmen, and no one ever comes to this marshy island. The house is invisible from the river, hidden as it is among the tangle of old rotting warehouses. You came here in a motorboat which was anchored beneath the rotting wharves behind Shan Yang's dive. Another boat will presently fetch my men who were sent to dispose of Joan La Tour."
"They may not find that so easy," commented the detective.
"Never fear. I know she summoned that hairy wolf, Khoda Khan, to her aid, and it's true that my men failed to slay him before he reached her. But I suppose it was a false sense of trust in the Afghan that caused you to make your appointment with Kleck. I rather expected you to remain with the foolish girl and try to protect her in your way."
Somewhere below them a gong sounded. Erlik Khan did not start, but there was a surprise in the lift of his head. He closed the black book.
"I have wasted enough time on you," he said. "Once before I bade you farewell in one of my dungeons. Then the fanaticism of a crazy Druse saved you. This time there will be no upset of my plans. The only men in this house are Mongols, who know no law but my will. I go, but you will not be lonely. Soon one will come to you."
And with a low, chilling laugh the phantom-like figure moved through the door and disappeared. Outside a lock clicked, and then there was stillness.
The silence was broken suddenly by a muffled scream. It came from somewhere below and was repeated half a dozen times. Harrison shuddered. No one who has ever visited an insane asylum could fail to recognize that sound. It was the shrieking of a mad woman. After these cries the silence seemed even more stifling and menacing.
Harrison swore to quiet his feelings, and again the velvet-capped head of the Mongol leered down at him through the trap.
"Grin, you yellow-bellied ape!" roared Harrison, tugging at his cords until the veins stood out on his temples. "If I could break these damned ropes I'd knock that grin around where your pigtail ought to be, you—" He went into minute details of the Mongol's ancestry, dwelling at length on the more scandalous phases of it, and in the midst of his noisy tirade he saw the leer change suddenly to a startled snarl. The head vanished from the trap and there came a sound like the blow of a butcher's cleaver.
Then another face was poked into the trap—a wild, bearded face, with blazing, bloodshot eyes, and surmounted by a disheveled turban.
"Sahib!" hissed the apparition.
"Khoda Khan!" ejaculated the detective, galvanized. "What the devil are you doing here?"
"Softly!" muttered the Afghan. "Let not the accursed ones hear!"
He tossed the loose end of a rope ladder down through the trap and came down in a rush, his bare feet making no sound as he hit the floor. He held his long knife in his teeth, and blood dripped from the point.
Squatting beside the detective he cut him free with reckless slashes that threatened to slice flesh as well as hemp. The Afghan was quivering with half-controlled passion. His teeth gleamed like a wolf's fangs amidst the tangle of his beard.
Harrison sat up, chafing his swollen wrists.
"Where's Joan? Quick, man, where is she?"
"Here! In this accursed den!"
"But—"
"That was she screaming a few minutes ago," broke in the Afghan, and Harrison's flesh crawled with a vague monstrous premonition.
"But that was a mad woman!" he almost whispered.
"The sahiba is mad," said Khoda Khan somberly. "Hearken, sahib, and then judge if the fault is altogether mine.
"After you left, the accursed ones let down a man from the roof on a rope. Him I knifed, and I slew three more who sought to force the doors. But when I returned to the sahiba, she knew me not. She fled from me into the street, and other devils must have been lurking nearby, because as she ran shrieking along the sidewalk, a big automobile loomed out of the fog and a Mongol stretched forth an arm and dragged her into the car, from under my very fingers. I saw his accursed yellow face by the light of a street lamp.
"Knowing she were better dead by a bullet than in their hands, I emptied my pistol after the car, but it fled like Shaitan the Damned from the face of Allah, and if I hit anyone in it, I know not. Then as I rent my garments and cursed the day of my birth—for I could not pursue it on foot— Allah willed that another automobile should appear. It was driven by a young man in evening clothes, returning from a revel, no doubt, and being cursed with curiosity he slowed down near the curb to observe my grief.
"So, praising Allah, I sprang in beside him and placing my knife point against his ribs bade him go with speed and he obeyed in great fear. The car of the damned ones was out of sight, but presently I glimpsed it again, and exhorted the youth to greater speed, so the machine seemed to fly like the steed of the Prophet. So, presently I saw the car halt at the river bank. I made the youth halt likewise, and he sprang out and fled in the other direction in terror.
"I ran through the darkness, hot for the blood of the accursed ones, but before I could reach the bank I saw four Mongols leave the car, carrying the memsahib who was bound and gagged, and they entered a motorboat and headed out into the river toward an island which lay on the breast of the water like a dark cloud.
"I cast up and down on the shore like a madman, and was about to leap in and swim, though the distance was great, when I came upon a boat chained to a pile, but one driven by oars. I gave praise to Allah and cut the chain with my knife—see the nick in the edge?—and rowed after the accursed ones with great speed.
"They were far ahead of me, but Allah willed it that their engine should sputter and cease when they had almost reached the island. So I took heart, hearing them cursing in their heathen tongue, and hoped to draw alongside and slay them all before they were aware of me. They saw me not in the darkness, nor heard my oars because of their own noises, but before I could reach them the accursed engine began again. So they reached a wharf on the marshy shore ahead of me, but they lingered to make the boat fast, so I was not too far behind them as they bore the memsahib through the shadows of the crumbling shacks which stood all about.
"Then I was hot to overtake and slay them, but before I could come up with them they had reached the door of a great stone house—this one, sahib—set in a tangle of rotting buildings. A steel fence surrounded it, with razor-edged spearheads set along the top but by Allah, that could not hinder a lifter of the Khyber! I went over it without so much as tearing my garments. Inside was a second wall of stone, but it stood in ruins.
"I crouched in the shadows near the house and saw that the windows were heavily barred and the doors strong. Moreover, the lower part of the house is full of armed men. So I climbed a corner of the wall, and it was not easy, but presently I reached the roof which at that part is flat, with a parapet. I expected a watcher, and so there was, but he was too busy taunting his captive to see or hear me until my knife sent him to Hell. Here is his dagger; he bore no gun."
Harrison mechanically took the wicked, lean-bladed poniard.
"But what caused Joan to go mad?"
"Sahib, there was a broken wine bottle on the floor, and a goblet. I had no time to investigate it, but I know that wine must have been poisoned with the juice of the fruit called the black pomegranate. She can not have drunk much, or she would have died frothing and champing like a mad dog. But only a little will rob one of sanity. It grows in the jungles of Indo-China, and white men say it is a lie. But it is no lie; thrice I have seen men die after having drunk its juice, and more than once I have seen men, and women too, turn mad because of it. I have traveled in that hellish country where it grows."