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?”

“i’ll answer your question,” said wessex, and the fact did not escape the keen observing power of nicol brinn that the detective’s manner had grown guarded. “he informed mr. innes, his secretary, before setting out, that he was coming here to your chambers.”

nicol brinn stared blankly at the speaker. “he told him that? when?”

“yesterday.”

“that he was coming here?”

“he did.”

nicol brinn sat down again upon the settee. “detective inspector,” said he, “i give you my word of honour as a gentleman that i last saw mr. paul harley at ten-fifteen on wednesday night. since then, not only have i not seen him, but i have received no communication from him.”

the keen glance of the detective met and challenged the dull glance of the speaker. “i accept your word, sir,” said wessex, finally, and he sighed and scratched his chin in the manner of a man hopelessly puzzled.

silence fell again. the muted sounds of piccadilly became audible in the stillness. cabs and cars rolled by below, their occupants all unaware of the fact that in that long, museum-like room above their heads lay the key to a tragedy and the clue to a mystery.

“look here, sir,” said the detective, suddenly, “the result of mr. paul harley’s investigations right up to date has been placed in my hands, together with all his notes. i wonder if you realize the fact that, supposing mr. harley does not return, i am in repossession of sufficient evidence to justify me in putting you under arrest?”

“i see your point quite clearly,” replied nicol brinn. “i have seen my danger since the evening that mr. paul harley walked into this room: but i’ll confess i did not anticipate this particular development.”

“to get right down to business,” said wessex, “if mr. paul harley did not come here, where, in your idea, did he go?”

nicol brinn considered the speaker meditatively. “if i knew that,” said he, “maybe i could help. i told him here in this very room that the pair of us were walking on the edge of hell. i don’t like to say it, and you don’t know all it means, but in my opinion he has taken a step too far.”

detective inspector wessex stood up impatiently. “you have already talked in that strain to mr. harley,” he said, a bit brusquely. “mr. innes has reported something of the conversation to me. but i must ask you to remember that, whereas mr. paul harley is an unofficial investigator, i am an officer of the criminal investigation department, and figures of speech are of no use to me. i want facts. i want plain speaking. i ask you for help and you answer in parables. now perhaps i am saying too much, and perhaps i am not, but that mr. harley was right in what he believed, the circumstances of his present disappearance go to prove. he learned too much about something called fire-tongue.”

wessex spoke the word challengingly, staring straight into the eyes of nicol brinn, but the latter gave no sign, and wessex, concealing his disappointment, continued: “you know more about fire-tongue than you ever told mr. paul harley. all you know i have got to know. mr. harley has been kidnapped, perhaps done to death.”

“why do you say so?” asked nicol brinn, rapidly.

“because i know it is so. it does not matter how i know.”

“you are certain that his absence is not voluntary?”

“we have definite evidence to that effect.”

“i don’t expect you to be frank with me, detective inspector, but i’ll be as frank with you as i can be. i haven’t the slightest idea in the world where mr. harley is. but i have information which, if i knew where he was, would quite possibly enable me to rescue him.”

“provided he is alive!” added wessex, angrily.

“what leads you to suppose that he is not?”

“if he is alive, he is a prisoner.”

“good god!” said nicol brinn in a low voice. “it has come.” he took a step toward the detective. “mr. wessex,” he continued, “i don’t tell you to do whatever your duty indicates; i know you will do it. but in the interests of everybody concerned i have a request to make. have me watched if you like—i suppose that’s automatic. but whatever happens, and wherever your suspicions point, give me twenty-four hours. as i think you can see, i am a man who thinks slowly, but moves with a rush. you can believe me or not, but i am even more anxious than you are to see this thing through. you think i know what lies back of it all, and i don’t say that you are not right. but one thing you don’t know, and that thing i can’t tell you. in twenty-four hours i might be able to tell you. whatever happens, even if poor harley is found dead, don’t hamper my movements between now and this time tomorrow.”

wessex, who had been watching the speaker intently, suddenly held out his hand. “it’s a bet!” he said. “it’s my case, and i’ll conduct it in my own way.”

“mr. wessex,” replied nicol brinn, taking the extended hand, “i think you are a clever man. there are questions you would like to ask me, and there are questions i would like to ask you. but we both realize the facts of the situation, and we are both silent. one thing i’ll say: you are in the deadliest peril you have ever known. be careful. believe me i mean it. be very careful.”