Swacker was evidently waiting for an opportunity to interrupt, for, when Sergeant Heath had passed through the door, he at once stepped into the room.

    "The reporters are here, sir," he announced, with a wry face. "You said you'd see them at ten thirty."

    In response to a nod from his chief, he held open the door, and a dozen or more newspaper men came trooping in.

    "No questions, please, this morning," Markham begged pleasantly. "It's too early in the game. But I'll tell you all I know. . . . I agree with Sergeant Heath that the Odell murder was the work of a professional criminal—the same who broke into Arnheim's house on Park Avenue last summer."

    Briefly he told of Inspector Brenner's findings in connection with the chisel. "We've made no arrest, but one may be expected in the very near future. In fact, the police have the case well in hand but are going carefully in order to avoid any chance of an acquittal. We've already recovered some of the missing jewelry. . . ."

    He talked to the reporters for five minutes or so, but he made no mention of the testimony of the maid or the phone operators, and carefully avoided the mention of any names.

    When we were again alone, Vance chuckled admiringly.

    "A masterly evasion, my dear Markham! Legal training has its advantages—decidedly it has its advantages. . . . 'We've recovered some of the missing jewelry!' Sweet winged words! Not an untruth—oh, no!—but how deceivin'! Really, y' know, I must devote more time to the caressin' art of suggestio falsi and suppressio veri. You should be crowned with an anadem of myrtle."

    "Leaving all that to one side," Markham rejoined impatiently, "suppose you tell me, now that Heath's gone, what was in your mind when you applied your verbal voodooism to Skeel. What was all the conjurer-talk about dark closets, and alarums, and pressing thumbs, and peering through keyholes?"

    "Well, now, I didn't think my little chit-chat was so cryptic," answered Vance. "The recherché Tony was undoubtedly ambuscaded à la sourdine in the clothes press at some time during the fatal evening; and I was merely striving, in my amateurish way, to ascertain the exact hour of his concealment."

    "And did you?"

    "Not conclusively." Vance shook his head sadly. "Y' know, Markham, I'm the proud possessor of a theory—it's vague and obscure and unsubtantial; and it's downright unintelligible. And even if it were verified, I can't see how it would help us any, for it would leave the situation even more incomprehensible than it already is. . . . I almost wish I hadn't questioned Heath's Beau Nash. He upset my ideas frightfully."

    "From what I could gather, you seem to think it possible that Skeel witnessed the murder. That couldn't, by any stretch of the imagination, be your precious theory?"

    "That's part of it, anyway."

    "My dear Vance, you do astonish me!" Markham laughed outright. "Skeel, then, according to you, is innocent; but he keeps his knowledge to himself, invents an alibi, and doesn't even tattle when he's arrested. . . . It won't hold water."

    "I know," sighed Vance. "It's a veritable sieve. And yet, the notion haunts me—it rides me like a hag—it eats into my vitals."

    "Do you realize that this mad theory of yours presupposes that, when Spotswoode and Miss Odell returned from the theater, there were two men hidden in the apartment—two men unknown to each other—namely Skeel and your hypothetical murderer?"

    "Of course I realize it; and the thought of it is breaking down my reason."

    "Furthermore, they must have entered the apartment separately and hidden separately. . . . How, may I ask, did they get in? And how did they get out? And which one caused the girl to scream after Spotswoode had left? And what was the other one doing in the meantime? And if Skeel was a passive spectator, horrified and mute, how do you account for his breaking open the jewel case and securing the ring—?"

    "Stop! Stop! Don't torture me so," Vance pleaded. "I know I'm insane. Been given to hallucinations since birth; but—Merciful Heaven!—I've never before had one as crazy as this."

    "On that point at least, my dear Vance, we are in complete and harmonious agreement," smiled Markham.

    Just then Swacker came in and handed Markham a letter.

    "Brought by messenger, and marked 'immediate,'" he explained.

    The letter, written on heavy engraved stationery, was from Doctor Lindquist, and explained that between the hours of 11 P.M. and 1 A.M. on Monday night he had been in attendance on a patient at his sanitarium. It also apologized for his actions when asked regarding his whereabouts, and offered a wordy, but not particularly convincing, explanation of his conduct. He had had an unusually trying day, it seemed—neurotic cases were trying, at best—and the suddenness of our visit, together with the apparently hostile nature of Markham's questions, had completely upset him. He was more than sorry for his outburst, he said, and stood ready to assist in any way he could. It was unfortunate for all concerned, he added, that he had lost his temper, for it would have been a simple matter for him to explain about Monday night.

    "He has thought the situation over calmly," said Vance, "and hereby offers you a neat little alibi which, I think, you will have difficulty in shaking. . . . An artful beggar—like all these unbalanced pseudopsychiatrists. Observe: he was with a patient. To be sure! What patient? Why, one too ill to be questioned. . . . There you are. A cul-de-sac masquerading as an alibi. Not bad, what?"

    "It doesn't interest me overmuch." Markham put the letter away. "That pompous professional ass could never have got into the Odell apartment without having been seen; and I can't picture him sneaking in by devious means." He reached for some papers. . . . "And now, if you don't object, I'll make an effort to earn my $15,000 salary."

    But Vance, instead of making a move to go, sauntered to the table and opened a telephone directory.

    "Permit me a suggestion, Markham," he said, after a moment's search. "Put off your daily grind for a bit, and let's hold polite converse with Mr. Louis Mannix. Y' know, he's the only presumptive swain of the inconstant Margaret, so far mentioned, who hasn't been given an audience. I hanker to gaze upon him and hearken to his rune. He'd make the family circle complete, so to speak. . . . He still holds forth in Maiden Lane, I see; and it wouldn't take long to fetch him here."

    Markham had swung half round in his chair at the mention of Mannix's name. He started to protest, but he knew from experience that Vance's suggestions were not the results of idle whims; and he was silent for several moments weighing the matter. With practically every other avenue of inquiry closed for the moment, I think the idea of questioning Mannix rather appealed to him.

    "All right," he consented, ringing for Swacker; "though I don't see how he can help. According to Heath, the Odell girl gave him his congé a year ago."

    "He may still have hay on his horns, or, like Hotspur, be drunk with choler. You can't tell." Vance resumed his chair. "With such a name, he'd bear investigation ipso facto."

    Markham sent Swacker for Tracy; and when the latter arrived, suave and beaming, he was given instructions to take the district attorney's car and bring Mannix to the office.

    "Get a subpoena," said Markham; "and use it if necessary."

    Half an hour or so later Tracy returned.

    "Mr. Mannix made no difficulty about coming," he reported. "Was quite agreeable, in fact. He's in the waiting room now."

    Tracy was dismissed, and Mannix was ushered in.

    He was a large man, and he walked with the forced elasticity of gait which epitomizes the silent struggle of incipiently corpulent middle age to deny the onrush of the years and cling to the semblance of youth. He carried a slender wanghee cane; and his checkered suit, brocaded waistcoat, pearl-gray gaiters, and gaily beribboned Homburg hat gave him an almost foppish appearance. But these various indications of sportiveness were at once forgotten when one inspected his features. His small eyes were bright and crafty; his nose was bibative, and appeared disproportionately small above his thick, sensual lips and prognathous jaw. There was an oiliness and shrewdness in the man's manner which were at once repulsive and arresting.

    At a gesture from Markham he sat down on the edge of a chair, placing a podgy hand on each knee. His attitude was one of alert suspicion.

    "Mr. Mannix," said Markham, an engaging note of apology in his voice, "I am sorry to have discommoded you; but the matter in hand is both serious and urgent. . . . A Miss Margaret Odell was murdered night before last, and in the course of inquiries we learned that you had at one time known her quite well. It occurred to me that you might be in possession of some facts about her that would assist us in our investigation."

    A saponaceous smile, meant to be genial, parted the man's heavy lips.

    "Sure, I knew the Canary—a long time ago, y' understand." He permitted himself a sigh. "A fine, high-class girl, if I do say so. A good looker and a good dresser. Too damn bad she didn't go on with the show business. But"—he made a repudiative motion with his hand—"I haven't seen the lady, y' understand, for over a year—not to speak to, if you know what I mean."

    Mannix clearly was on his guard, and his beady little eyes did not once leave the district attorney's face.

    "You had a quarrel with her perhaps?" Markham asked the question incuriously.

    "Well, now, I wouldn't go so far as to say we quarreled. No." Mannix paused, seeking the correct word. "You might say we disagreed—got tired of the arrangement and decided to separate; kind of drifted apart. Last thing I told her was, if she ever needed a friend, she'd know where to find me."

    "Very generous of you," murmured Markham. "And you never renewed your little affair?"

    "Never—never. Don't remember ever speaking to her from that day to this."

    "In view of certain things I've learned, Mr. Mannix"—Markham's tone was regretful—"I must ask you a somewhat personal question. Did she ever make an attempt to blackmail you?"

    Mannix hesitated, and his eyes seemed to grow even smaller, like those of a man thinking rapidly.

    "Certainly not!" he replied, with belated emphasis. "Not at all. Nothing of the kind." He raised both hands in protest against the thought. Then he asked furtively: "What gave you such an idea?"

    "I have been told," explained Markham, "that she had extorted money from one or two of her admirers."

    Mannix made a wholly unconvincing grimace of astonishment. "Well well! You don't tell me! Can it be possible?" He peered shrewdly at the district attorney. "Maybe it was Charlie Cleaver she blackmailed—yes?"

    Markham picked him up quickly.

    "Why do you say Cleaver?"

    Again Mannix waved his thick hand, this time deprecatingly.

    "No special reason, y' understand. Just thought it might be him. . . . No special reason."

    "Did Cleaver ever tell you he'd been blackmailed?"

    "Cleaver tell me? . . . Now, I ask you, Mr. Markham: why should Cleaver tell me such a story—why should he?"

    "And you never told Cleaver that the Odell girl had blackmailed you?"

    "Positively not!" Mannix gave a scornful laugh which was far too theatrical to have been genuine. "Me tell Cleaver I'd been blackmailed? Now, that's funny, that is."

    "Then, why did you mention Cleaver a moment ago?"

    "No reason at all—like I told you. . . . He knew the Canary; but that ain't no secret."

    Markham dropped the subject. "What do you know about Miss Odell's relations with a Doctor Ambroise Lindquist?"

    Mannix was now obviously perplexed. "Never heard of him—no, never. She didn't know him when I was taking her around."

    "Whom else besides Cleaver did she know well?"

    Mannix shook his head ponderously.

    "Now, that I couldn't say—positively I couldn't say. Seen her with this man and that, same as everybody saw her; but who they were I don't know—absolutely."

    "Ever hear of Tony Skeel?" Markham quickly leaned over and met the other's gaze inquiringly.

    Once more Mannix hesitated, and his eyes glittered calculatingly. "Well, now that you ask me, I believe I did hear of the fellow. But I couldn't swear to it, y' understand. . . . What makes you think I heard of this Skeel fellow?"

    Markham ignored the question.

    "Can you think of no one who might have borne Miss Odell a grudge, or had cause to fear her?"

    Mannix was volubly emphatic on the subject of his complete ignorance of any such person; and after a few more questions, which elicited only denials, Markham let him go.

    "Not bad at all, Markham old thing—eh, what?" Vance seemed pleased with the conference. "Wonder why he's so coy? Not a nice person, this Mannix. And he's so fearful lest he be informative. Again, I wonder why. He was so careful—oh, so careful."

    "He was sufficiently careful, at any rate, not to tell us anything," declared Markham gloomily.

    "I shouldn't say that, don't y' know." Vance lay back and smoked placidly. "A ray of light filtered through here and there. Our fur-importing philogynist denied he'd been blackmailed—which was obviously untrue—and tried to make us believe that he and the lovely Margaret cooed like turtledoves at parting—Tosh! . . . And then, that mention of Cleaver. That wasn't spontaneous—dear me, no. Brother Mannix and spontaneity are as the poles apart. He had a reason for bringing Cleaver in; and I fancy that if you knew what that reason was, you'd feel like flinging roses riotously, and that sort of thing. Why Cleaver? That secret-de-Polichinelle explanation was a bit weak. The orbits of these two paramours cross somewhere. On that point, at least, Mannix inadvertently enlightened us. . . . Moreover, it's plain that he doesn't know our fashionable healer with the satyr ears. But, on the other hand, he's aware of the existence of Mr. Skeel, and would rather like to deny the acquaintance. . . . So—voilà l'affaire. Plenty of information; but—my word!—what to do with it?"

    "I give it up," acknowledged Markham hopelessly.

    "I know; it's a sad sad world," Vance commiserated him. "But you must face the olla podrida with a bright eye. It's time for lunch, and a fillet of sole Marguéry will cheer you no end."

    Markham glanced at the clock and permitted himself to be led to the Lawyers Club.