detective sergeant stokes was a big, dark, florid man, the word “constable” written all over him. indeed, as wessex had complained more than once, the mere sound of stokes’s footsteps was a danger signal for any crook. his respect for his immediate superior, the detective inspector, was not great. the methods of wessex savoured too much of the french school to appeal to one of stokes’s temperament and outlook upon life, especially upon that phase of life which comes within the province of the criminal investigator.

wessex’s instructions with regard to nicol brinn had been succinct: “watch mr. brinn’s chambers, make a note of all his visitors, but take no definite steps respecting him personally without consulting me.”

armed with these instructions, the detective sergeant had undertaken his duties, which had proved more or less tedious up to the time that a fashionably attired woman of striking but unusual appearance had inquired of the hall porter upon which floor mr. nicol brinn resided.

in her manner the detective sergeant had perceived something furtive. there was a hunted look in her eyes, too.

when, at the end of some fifteen or twenty minutes, she failed to reappear, he determined to take the initiative himself. by intruding upon this prolonged conference he hoped to learn something of value. truth to tell, he was no master of finesse, and had but recently been promoted from an east end district where prompt physical action was of more value than subtlety.

as a result, then, he presently found himself in the presence of the immovable hoskins; and having caused his name to be announced, he was requested to wait in the lobby for one minute. exactly one minute had elapsed when he was shown into that long, lofty room, which of late had been the scene of strange happenings.

nicol brinn was standing before the fireplace, hands clasped behind him, and a long cigar protruding from the left corner of his mouth. no one else was present, so far as the detective could see, but he glanced rapidly about the room in a way which told the man who was watching that he had expected to find another present. he looked into the unfathomable, light blue eyes of nicol brinn, and became conscious of a certain mental confusion.

“good evening, sir,” he said, awkwardly. “i am acting in the case concerning the disappearance of mr. paul harley.”

“yes,” replied brinn.

“i have been instructed to keep an eye on these chambers.”

“yes,” repeated the high voice.

“well, sir”—again he glanced rapidly about-“i don’t want to intrude more than necessary, but a lady came in here about half an hour ago.”

“yes,” drawled brinn. “it’s possible.”

“it’s a fact,” declared the detective sergeant. “if it isn’t troubling you too much, i should like to know that lady’s name. also, i should like a chat with her before she leaves.”

“can’t be done,” declared nicol brinn. “she isn’t here.”

“then where is she?”

“i couldn’t say. she went some time ago.”

stokes stood squarely before nicol brinn—a big, menacing figure; but he could not detect the slightest shadow of expression upon the other’s impassive features. he began to grow angry. he was of that sanguine temperament which in anger acts hastily.

“look here, sir,” he said, and his dark face flushed. “you can’t play tricks on me. i’ve got my duty to do, and i am going to do it. ask your visitor to step in here, or i shall search the premises.”

nicol brinn replaced his cigar in the right corner of his mouth: “detective sergeant stokes, i give you my word that the lady to whom you refer is no longer in these chambers.”

stokes glared at him angrily. “but there is no other way out,” he blustered.

“i shall not deal with this matter further,” declared brinn, coldly. “i may have vices, but i never was a liar.”

“oh,” muttered the detective sergeant, taken aback by the cold incisiveness of the speaker. “then perhaps you will lead the way, as i should like to take a look around.”

nicol brinn spread his feet more widely upon the hearthrug. “detective sergeant stokes,” he said, “you are not playing the game. inspector wessex passed his word to me that for twenty-four hours my movements should not be questioned or interfered with. how is it that i find you here?”

stokes thrust his hands in his pockets and coughed uneasily. “i am not a machine,” he replied; “and i do my own job in my own way.”

“i doubt if inspector wessex would approve of your way.”

“that’s my business.”

“maybe, but it is no affair of yours to interfere with private affairs of mine, detective sergeant. see here, there is no lady in these chambers. secondly, i have an appointment at nine o’clock, and you are detaining me.”

“what’s more,” answered stokes, who had now quite lost his temper, “i intend to go on detaining you until i have searched these chambers and searched them thoroughly.”

nicol brinn glanced at his watch. “if i leave in five minutes, i’ll be in good time,” he said. “follow me.”

crossing to the centre section of a massive bookcase, he opened it, and it proved to be a door. so cunning was the design that the closest scrutiny must have failed to detect any difference between the dummy books with which it was decorated, and the authentic works which filled the shelves to right and to left of it. within was a small and cosy study. in contrast with the museum-like room out of which it opened, it was furnished in a severely simple fashion, and one more experienced in the study of complex humanity than detective sergeant stokes must have perceived that here the real nicol brinn spent his leisure hours. above the mantel was a life-sized oil painting of mrs. nicolas brinn; and whereas the great room overlooking piccadilly was exotic to a degree, the atmosphere of the study was markedly american.

palpably there was no one there. nor did the two bedrooms, the kitchen, and the lobby afford any more satisfactory evidence. nicol brinn led the way back from the lobby, through the small study, and into the famous room where the egyptian priestess smiled eternally. he resumed his place upon the hearthrug. “are you satisfied, detective sergeant?”

“i am!” stokes spoke angrily. “while you kept me talking, she slipped out through that study, and down into the street.”

“ah,” murmured nicol brinn.

“in fact, the whole business looks very suspicious to me,” continued the detective.

“sorry,” drawled brinn, again consulting his watch. “the five minutes are up. i must be off.”

“not until i have spoken to scotland yard, sir.”

“you wish to speak to scotland yard?”

“i do,” said stokes, grimly.

nicol brinn strode to the telephone, which stood upon a small table almost immediately in front of the bookcase. the masked door remained ajar.

“you are quite fixed upon detaining me?”

“quite,” said stokes, watching him closely.

in one long stride brinn was through the doorway, telephone in hand! before stokes had time to move, the door closed violently, in order, no doubt, to make it shut over the telephone cable which lay under it!

detective sergeant stokes fell back, gazed wildly at the false books for a moment, and then, turning, leaped to the outer door. it was locked!

in the meanwhile, nicol brinn, having secured the door which communicated with the study, walked out into the lobby where hoskins was seated. hoskins stood up.

“the lady went, hoskins?”

“she did, sir.”

nicol brinn withdrew the key from the door of the room in which detective sergeant stokes was confined. stokes began banging wildly upon the panels from within.

“that row will continue,” nicol brinn said, coldly; “perhaps he will shout murder from one of the windows. you have only to say you had no key. i am going out now. the light coat, hoskins.”

hoskins unemotionally handed coat, hat, and cane to his master and, opening the front door, stood aside. the sound of a window being raised became audible from within the locked room.

“probably,” added nicol brinn, “you will be arrested.”

“very good, sir,” said hoskins. “good-night, sir...”