Nayland Smith studied the disc with keen interest. "There's some sort of hieroglyphic stamped on the metal," Malcolm pointed out. "I wonder what it means?"
"I think I know," Sir Denis answered. "With your permission, Inspector, I'll take this thing with me for expert examination. There's nothing more to be done here, Forbes. First score to Dr Fu Manchu. A further chat with your charming acquaintance, Miss Rostov, might bring a little light on things."
In Mrs Sefton's sitting room the dark girl reclined on the sofa as they had left her. She was alone. A cup of tea stood on a table near her. She raised her eyelids languidly but otherwise did not move.
"Fm sorry to have detained you." Nayland Smith spoke drily. "But I thought you might be able to give me some information about this."
He extended the metal disc on his open palm.
The effect was electrical. The girl sprang up in one lithe movement, her remarkable eyes widely opened.
"Ahl It is mine! Thank you very much."
"Yours?" Nayland Smith snapped. "Then why was it chained about his neck?"
"There is a way to unfasten the chain. It is mine. Please give it to me."
"If that is the case, you shall have it — but not yet. What is it?"
"It is an Eastern charm. To me," suddenly her eyes were brimming with tears, "it means so much. To you it can mean nothing."
"ITm, very interesting." He dropped the disc back into his pocket. "I should be obliged. Miss Rostov, if you would give Mr Forbes your address while I go and arrange for you to be driven home."
Nayland Smith went out, closing the door. And at the same moment that he did so, the girl moved forward and clutched Malcolm, raising tearful appealing eyes to him.
"Listen to me," she whispered. "You must listen to me! Persuade him to give me my amulet."
Malcolm tried, gently, to detach her hands. "I assure you, Sir Denis will do so. He—"
"My name is Nadia. Be my friend. I have no one but you to help me."
Malcolm's natural chivalry, and Nadia's beauty, might have conquered discretion if he had had it in his power to do as she asked. But she asked the impossible.
"I'd gladly help you, Nadia, but Sir Denis wouldn't listen to me."
She drooped against him, her head on his shoulder. Her hair Shad a subtle fragrance.
"I am sorry. I think you would help me, if you could."
Footsteps sounded on the stairs. Nadia drew back.
Malcolm pulled out a note-book awkwardly, and tried to force his mind back to normality.
"Please give me your address now, Nadia."
"Eighty-five Westboume Terrace," she told him in a toneless voice.
The door opened and Nayland Smith came in, followed by West.
"Mr West will drive you home. Miss Rostov. You have the address, Forbes?"
On the way back from Clapham, Sir Denis said: "I hoped your friend, Nadia, might give something more away to you if I offered her the chance, but as a Don Juan you're fired, Forbes! She's some sort of Eurasian, and although devilishly attractive, I don't believe for a moment that there was any real attachment between her and Kenealy. We have what she came tonight to recover — the disc."
"That's clear, Sir Denis. But have you any idea what it is?"
"Except that it's stamped with the sign of the Si-Fan, none…"
"Sign of the Si-Pan? What is the Si-Fan?"
Nayland Smith laughed shortly. "It's a world-wide secret society of which Dr Fu Manchu is president."
"Then why did Kenealy —?"
"The disc chained around his neck? Top marks to a brave man. He had joined the Si-Fan."
"Good heavens!"
"He had brains and nerve. But he must have slipped up. He was expecting another visitor tonight. And it wasn't Nadia. To the end, he hoped to bluff it out. Hence his destruction of all evidence against him. Is this clear to you, Forbes?"
"Yes — now it is. And it's horrible."
"The ways of Dr Fu Manchu are always horrible."
The door of Nayland Smith's flat in Whitehall Court was opened by a manservant whose prominent jaw and grim expression inspired confidence.
"Good evening, Begby," Sir Denis said. "Any messages?" "Yes, sir. A Mr West reported at ten-thirty-three."
"Good. Drinks in the study."
A moment later Malcolm was in a room which he could have recognised with his eyes shut from its overpowering smell of tobacco. As Sir Denis began to re-fill his hot pipe from a very large pouch, Begby came in with whisky and soda on a tray.
Begby put the drinks down, then:
"Going by way of Bayswater Road with this lady, Mr West got hit by a heavy truck that came out of a side-turning. He was knocked out, but not hurt, sir. The lady had vanished when he come round. They hung on to the truck driver."
"Thanks, Begby." Nayland Smith poured out drinks as his servant withdrew, and shrugged his shoulders. "You see, Forbes? We're dealing with Fu Manchu."
He sat at his large, orderly desk, putting the mysterious disc on the blotting-pad; began to study it through a powerful lens. Malcolm crossed and bent over his shoulder.
"Might I take a look. Sir Denis?"
Nayland Smith handed the lens to Malcolm and presently:
"The hieroglyphic means nothing to me," Malcolm confessed; "but what metal is this thing made of?"
He picked the disc up, weighing it in his hand, when Begby rapped on the study door, came in and announced in a queerly muffled voice:
"Dr Fu Manchu, sir!"
"What!"
Nayland Smith sprang up. Malcolm slipped the disc into his pocket. "At last you have him!" he whispered.
"Show Dr Fu Manchu in here," Sir Denis said quietly, sat down and opened a desk drawer.
A tall figure came into the study, that of a man who wore a black overcoat with a heavy astrakhan collar and who carried a black hat. Begby retired and closed the door.
Malcolm became lost in fascination at the most wonderful face he had ever seen. The high, scholarly brow, the incredibly long, green eyes, the lined, intellectual features, the tremendous aura of power of Dr Fu Manchu. He stood, stock-still, watching him.
"Good evening. Sir Denis." It was a high, metallic voice, the words precisely spoken. "This gentleman I assume to be Mr Malcolm Forbes, in whose career you take an interest. You may close the desk drawer. There will be no need for the revolver you keep there. I have taken the liberty of calling upon you only for the purpose of recovering a small metal disc which I believe you have in your possession."
Nayland Smith, his face set like a mask, watched him but did not speak.
"As I note a hand-lens there, perhaps the disc you have been examining is in your desk. Would you be good enough to let me see it?"
Malcolm, uneasily, slipped his hand into his coat pocket. The terrifying green eyes were flashed in his direction at the very instant that Nayland Smith, his elbow resting on his desk, covered Dr Fu Manchu with a Service revolver.
"Dr Fu Manchu, you are under arrest."
But Dr Fu Manchu, his manner unperturbed, dropped the soft, black hat on the carpet and raised his hand. He held a small dial studded with several buttons.
"Take your hand from your pocket, Mr Forbes," he said si-bilantly. "I know that the disc is there. I have my finger on the button which will connect it with the power centre. Your shot would come too late. Sir Denis, to save Mr Forbes. You have seen tonight how enemies of the SiFan die."
Malcolm, seeing again the grey face of Sergeant Kenealy, obeyed. His forehead was damp. Nayland Smith still covered Fu Manchu.
"Put away your obsolete weapon. Sir Denis," the mocking voice went on, "unless you really believe my death to be worth the life of your friend. I have conquered a new vibration. The disc in Mr Forbes' pocket is tuned to it. A recruit to our order carries such a disc. If he proves unworthy, he is removed."