It was close upon noon, but Nicol Brinn had not yet left his chambers. From that large window which overlooked Piccadilly he surveyed the prospect with dull, lack-lustre eyes. His morning attire was at least as tightly fitting as that which he favoured in the evening, and now, hands clasped behind his back and an unlighted cigar held firmly in the left corner of his mouth, he gazed across the park with a dreamy and vacant regard. One very familiar with this strange and taciturn man might have observed that his sallow features looked even more gaunt than usual. But for any trace of emotion in that stoic face the most expert physiognomist must have sought in vain.  
Behind the motionless figure the Alaskan ermine and Manchurian leopards stared glassily across the room. The flying lemur continued apparently to contemplate the idea of swooping upon the head of the tigress where she crouched upon her near-by pedestal. The death masks grinned; the Egyptian priestess smiled. And Nicol Brinn, expressionless, watched the traffic in Piccadilly.
 
There came a knock at the door.
 
“In,” said Nicol Brinn.
 
Hoskins, his manservant, entered: “Detective Inspector Wessex would like to see you, sir.”
 
Nicol Brinn did not turn around. “In,” he repeated.
 
Silently Hoskins retired, and, following a short interval, ushered into the room a typical detective officer, a Scotland Yard man of the best type. For Detective Inspector Wessex no less an authority than Paul Harley had predicted a brilliant future, and since he had attained to his present rank while still a comparatively young man, the prophecy of the celebrated private investigator was likely to be realized. Nicol Brinn turned and bowed in the direction of a large armchair.
 
“Pray sit down, Inspector,” he said.
 
The high, monotonous voice expressed neither surprise nor welcome, nor any other sentiment whatever.
 
Detective Inspector Wessex returned the bow, placed his bowler hat upon the carpet, and sat down in the armchair. Nicol Brinn seated himself upon a settee over which was draped a very fine piece of Persian tapestry, and stared at his visitor with eyes which expressed nothing but a sort of philosophic stupidity, but which, as a matter of fact, photographed the personality of the man indelibly upon that keen brain.
 
Detective Inspector Wessex cleared his throat and did not appear to be quite at ease.
 
“What is it?” inquired Nicol Brinn, and proceeded to light his cigar.
 
“Well, sir,” said the detective, frankly, “it’s a mighty awkward business, and I don’t know just how to approach it.”
 
“Shortest way,” drawled Nicol Brinn. “Don’t study me.”
 
“Thanks,” said Wessex, “I’ll do my best. It’s like this”—he stared frankly at the impassive face: “Where is Mr. Paul Harley?”
 
Nicol Brinn gazed at the lighted end of his cigar meditatively for a moment and then replaced it in the right and not in the left corner of his mouth. Even to the trained eye of the detective inspector he seemed to be quite unmoved, but one who knew him well would have recognized that this simple action betokened suppressed excitement.
 
“He left these chambers at ten-fifteen on Wednesday night,” replied the American. “I had never seen him before and I have never seen him since.”
 
“Sure?”
 
“Quite.”
 
“Could you swear to it before a jury?”
 
“You seem to doubt my word.”
 
Detective Inspector Wessex stood up. “Mr. Brinn,” he said, “I am in an awkward corner. I know you for a man with a fine sporting reputation, and therefore I don’t doubt your word. But Mr. Paul Harley disappeared last night.”
 
At last Nicol Brinn was moved. A second time he took the cigar from his mouth, gazed at the end reflectively, and then hurled the cigar across the room into the hearth. He stood up, walked to a window, and stared out. “Just sit quiet a minute,” came the toneless voice. “You’ve hit me harder than you know. I want to think it out.”
 
At the back of the tall, slim figure Detective Inspector Wessex stared with a sort of wonder. Mr. Nicol Brinn of Cincinnati was a conundrum which he found himself unable to catalogue, although in his gallery of queer characters were many eccentric and peculiar. If Nicol Brinn should prove to be crooked, then automatically he became insane. This Wessex had reasoned out even before he had set eyes upon the celebrated American traveller. His very first glimpse of Nicol Brinn had confirmed his reasoning, except that the cool, calm strength of the man had done much to upset the theory of lunacy.
 
Followed an interval of unbroken silence. Not even the ticking of a clock could be heard in that long, singularly furnished apartment. Then, as the detective continued to gaze upon the back of Mr. Nicol Brinn, suddenly the latter turned.
 
“Detective Inspector Wessex,” he said, “there has been a cloud hanging over my head for seven years. That cloud is going to burst very soon, and it looks as if it were going to do damage.”
 
“I don’t understand you, sir,” replied the detective, bluntly. “But I have been put in charge of the most extraordinary case that has ever come my way and I’ll ask you to make yourself as clear as possible.”
 
“I’ll do all I can,” Nicol Brinn assured him. “But first tell me something: Why have you come to me for information in respect to Mr. Paul Harley?”
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