I found Markham pacing restlessly up and down, his hat and gloves thrown carelessly on the centre-table. As I entered he halted and looked at me with harassed eyes. He was a moderately tall man, clean-shaven, gray-haired, and firmly set up. His appearance was distinguished, and his manner courteous and kindly. But beneath his gracious exterior there was an aggressive sternness, an indomitable, grim strength, that gave one the sense of dogged efficiency and untiring capability.

“Good morning, Van,” he greeted me, with impatient perfunctoriness. “There’s been another half-world murder—the worst and ugliest thus far. …” He hesitated, and regarded me searchingly. “You recall my chat with Vance at the club the other night? There was something damned prophetic in his remarks. And you remember I half promised to take him along on the next important case. Well, the case has broken—with a vengeance. Margaret Odell, whom they called the Canary, has been strangled in her apartment; and from what I just got over the phone, it looks like another night-club affair. I’m headed for the Odell apartment now. … What about rousing out the sybarite?”

“By all means,” I agreed, with an alacrity which, I fear, was in large measure prompted by purely selfish motives. The Canary! If one had sought the city over for a victim whose murder would stir up excitement, there could have been but few selections better calculated to produce this result.

Hastening to the door, I summoned Currie, and told him to call Vance at once.

“I’m afraid, sir—” began Currie, politely hesitant.

“Calm your fears,” cut in Markham. “I’ll take all responsibility for waking him at this indecent hour.”

Currie sensed an emergency and departed.

A minute or two later Vance, in an elaborately embroidered silk kimono and sandals, appeared at the living-room door.

“My word!” he greeted us, in mild astonishment, glancing at the clock. “Haven’t you chaps gone to bed yet?”

He strolled to the mantel, and selected a gold-tipped Régie cigarette from a small Florentine humidor.

Markham’s eyes narrowed: he was in no mood for levity.

“The Canary has been murdered,” I blurted out.

Vance held his wax vesta poised, and gave me a look of indolent inquisitiveness. “Whose canary?”

“Margaret Odell was found strangled this morning,” amended Markham brusquely. “Even you, wrapped in your scented cotton-wool, have heard of her. And you can realize the significance of the crime. I’m personally going to look for those footprints in the snow; and if you want to come along, as you intimated the other night, you’ll have to get a move on.”

Vance crushed out his cigarette.

“Margaret Odell, eh?—Broadway’s blonde Aspasia—or was it Phryne who had the coiffure d’or[17] … Most distressin’!” Despite his offhand manner, I could see he was deeply interested. “The base enemies of law and order are determined to chivvy you most horribly, aren’t they, old dear? Deuced inconsiderate of ’em! … Excuse me while I seek habiliments suitable to the occasion.”

He disappeared into his bedroom, while Markham took out a large cigar and resolutely prepared it for smoking, and I returned to the library to put away the papers on which I had been working.

In less than ten minutes Vance reappeared, dressed for the street.

“Bien, mon vieux[18],” he announced gaily, as Currie handed him his hat and gloves and a malacca cane. “Allons-y![19]”

We rode up-town along Madison Avenue, turned into Central Park, and came out by the West 72d Street entrance. Margaret Odell’s apartment was at 184 West 71