“I can't help thinking, Chief Inspector,” said the officer in charge at Limehouse Station, “that you take unnecessary risks.”  
“Can't you?” said Kerry, tilting his bowler farther forward and staring truculently at the speaker.
 
“No, I can't. Since you cleaned up the dope gang down here you've been a marked man. These murders in the Chinatown area, of which this one to-night makes the third, have got some kind of big influence behind them. Yet you wander about in the fog without even a gun in your pocket.”
 
“I don't believe in guns,” rapped Kerry. “My bare hands are good enough for any yellow smart in this area. And if they give out I can kick like a mule.”
 
The other laughed, shaking his head.
 
“It's silly, all the same,” he persisted. “The man who did the job out there in the fog to-night might have knifed you or shot you long before you could have got here.”
 
“He might,” snapped Kerry, “but he didn't.”
 
Yet, remembering his wife, who would be waiting for him in the cosy sitting-room he knew a sudden pang. Perhaps he did take unnecessary chances. Others had said so. Hard upon the thought came the memory of his boy, and of the telephone message which the episodes of the night had prevented him from sending.
 
He remembered, too, something which his fearless nature had prompted him to forget: he remembered how, just as he had arisen from beside the body of the murdered man, oblique eyes had regarded him swiftly out of the fog. He had lashed out with a boxer's instinct, but his knuckles had encountered nothing but empty air. No sound had come to tell him that the thing had not been an illusion. Only, once again, as he groped his way through the shuttered streets of Chinatown and the silence of the yellow mist, something had prompted him to turn; and again he had detected the glint of oblique eyes, and faintly had discerned the form of one who followed him.
 
Kerry chewed viciously, then:
 
“I think I'll 'phone the wife,” he said abruptly. “She'll be expecting me.”
 
Almost before he had finished speaking the 'phone bell rang, and a few moments later:
 
“Someone to speak to you, Chief Inspector,” cried the officer in charge.
 
“Ah!” exclaimed Kerry, his fierce eyes lighting up. “That will be from home.”
 
“I don't think so,” was the reply. “But see who it is.”
 
“Hello!” he called.
 
He was answered by an unfamiliar voice, a voice which had a queer, guttural intonation. It was the sort of voice he had learned to loathe.
 
“Is that Chief Inspector Kerry?”
 
“Yes,” he snapped.
 
“May I take it that what I have to say will be treated in confidence?”
 
“Certainly not.”
 
“Think again, Chief Inspector,” the voice continued. “You are a man within sight of the ambition of years, and although you may be unaware of the fact, you stand upon the edge of a disaster. I appreciate your sense of duty and respect it. But there are times when diplomacy is a more potent weapon than force.”
 
Kerry, listening, became aware that the speaker was a man of cultured intellect. He wondered greatly, but:
 
“My time is valuable,” he said rapidly. “Come to the point. What do you want and who are you?”
 
“One moment, Chief Inspector. An opportunity to make your fortune without interfering with your career has come in your way. You have obtained possession of what you believe to be a clue to a murder.”
 
The voice ceased, and Kerry remaining silent, immediately continued:
 
“Knowing your personal character, I doubt if you have communicated the fact of your possessing this evidence to anyone else. I suggest, in your own interests, that before doing so you interview me.”
 
Kerry thought rapidly, and then:
 
“I don't say you're right,” he rapped back. “But if I come to see you, I shall leave a sealed statement in possession of the officer in charge here.”
 
“To this I have no objection,” the guttural voice replied, “but I beg of you to bring the evidence with you.”
 
“I'm not to be bought,” warned Kerry. “Don't think it and don't suggest it, or when I get to you I'll break you in half.”
 
His red moustache positively bristled, and he clutched the receiver so tightly that it quivered against his ear.
 
“You mistake me,” replied the speaker. “My name is Zani Chada. You know where I live. I shall not detain you more than five minutes if you will do me the honour of calling upon me.”
 
Kerry chewed furiously for ten momentous seconds, then:
 
“I'll come!” he said.
 
He replaced the receiver on the hook, and, walking across to the charge desk, took an official form and a pen. On the back of the form he scribbled rapidly, watched with curiosity by the officer in charge.
 
“Give me an envelope,” he directed.
 
An envelope was found and handed to him. He placed the paper in the envelope, gummed down the lapel, and addressed it in large, bold writing to the Assistant Commissioner of the Criminal Investigation Department, who was his chief. Finally:
 
“I'm going out,” he explained.
 
“After what I've said?”
 
“After what you've said. I'm going out. If I don't come back or don't telephone within the next hour, you will know what to do with this.”
 
The Limehouse official stared perplexedly.
 
“But meanwhile,” he protested, “what steps am I to take about the murder? Durham will be back with the body at any moment now, and you say you've got a clue to the murderer.”
 
“I have,” said Kerry, “but I'm going to get definite evidence. Do nothing until you hear from me.”
 
“Very good,” answered the other, and Kerry, tucking his malacca cane under his arm, strode out into the fog.
 
His knowledge of the Limehouse area was extensive and peculiar, so that twenty minutes later, having made only one mistake in the darkness, he was pressing an electric bell set beside a door which alone broke the expanse of a long and dreary brick wall, lining a street which neither by day nor night would have seemed inviting to the casual visitor.
 
The door was opened by a Chinaman wearing national dress, revealing a small, square lobby, warmly lighted and furnished Orientally. Kerry stepped in briskly.
 
“I want to see Mr. Zani Chada. Tell h............