"The Commedia dell' Arte," murmured Poirot. "I know."

"Anyway, the costumes were copied from a set of china figures forming part of Eustace Beltane's collection. Lord Cronshaw was Harlequin; Beltane was Punchinello; Mrs. Mallaby matched him as Pulcinella; the Davidsons were Pierrot and Pierette; and Miss Courtenay, of course, was Columbine. Now, quite early in the evening it was apparent that there was something wrong. Lord Cronshaw was moody and strange in his manner. When the party met together for supper in a small private room engaged by the host, everyone noticed that he and Miss Courtenay were no longer on speaking terms. She had obviously been crying, and seemed on the verge of hysterics. The meal was an uncomfortable one, and as they all left the supper room, she turned to Chris Davidson and requested him audibly to take her home, as she was 'sick of the ball.' The young actor hesitated, glancing at Lord Cronshaw, and finally drew them both back to the supper room.

"But all his efforts to secure a reconciliation were unavailing, and he accordingly got a taxi and escorted the now weeping Miss Courtenay back to her flat. Although obviously very much upset, she did not confide in him, merely reiterating again and again that she would 'make old Cronch sorry for this!' That is the only hint we have that her death might not have been accidental, and it's precious little to go upon. By the time Davidson had quieted her down somewhat, it was too late to return to the Colossus Hall, and Davidson accordingly went straight home to his flat in Chelsea, where his wife arrived shortly afterwards, bearing the news of the terrible tragedy that had occurred after his departure.

"Lord Cronshaw, it seems, became more and more moody as the ball went on. He kept away from his party, and they hardly saw him during the rest of the evening. It was about one-thirty a.m., just before the grand cotillion when everyone was to unmask, that Captain Digby, a brother officer who knew his disguise, noticed him standing in a box gazing down on the scene.

" 'Hullo, Cronch!' he called. 'Come down and be sociable! What are you moping about up there for like a boiled owl? Come along; there's a good old rag coming on now.'

" 'Right!' responded Cronshaw. 'Wait for me, or I'll never find you in the crowd.'

"He turned and left the box as he spoke. Captain Digby, who had Mrs. Davidson with him, waited. The minutes pa.s.sed, but Lord Cronshaw did not appear. Finally Digby grew impatient.

" 'Does the fellow think we're going to wait all night for him?' he exclaimed.

"At that moment Mrs. Mallaby joined them, and they explained the situation.

" 'Say, now,' cried the pretty widow vivaciously, 'he's like a bear with a sore head tonight. Let's go right away and rout him out.'

"The search commenced, but met with no success until it occurred to Mrs. Mallaby that he might possibly be found in the room where they had supped an hour earlier. They made their way there. What a sight met their eyes! There was Harlequin, sure enough, but stretched on the ground with a table-knife in his heart!"

j.a.pp stopped, and Poirot nodded, and said with the relish of the specialist: "Une belle affaire! And there was no clue as to the perpetrator of the deed? But how should there be!"

"Well," continued the inspector, "you know the rest. The tragedy was a double one. Next day there were headlines in all the papers, and a brief statement to the effect that Miss Courtenay, the popular actress, had been discovered dead in her bed, and that her death was due to an overdose of cocaine. Now, was it accident or suicide? Her maid, who was called upon to give evidence, admitted that Miss Courtenay was a confirmed taker of the drug, and a verdict of accidental death was returned. Nevertheless we can't leave the possibility of suicide out of account. Her death is particularly unfortunate, since it leaves us no clue now to the cause of the quarrel the preceding night. By the way, a small enamel box was found on the dead man. It had Coco written across it in diamonds, and was half full of cocaine. It was identified by Miss Courtenay's maid as belonging to her mistress, who nearly always carried it about with her, since it contained her supply of the drug to which she was fast becoming a slave."

"Was Lord Cronshaw himself addicted to the drug?"

"Very far from it. He held unusually strong views on the subject of dope."

Poirot nodded thoughtfully.

"But since the box was in his possession, he knew that Miss Courtenay took it. Suggestive, that, is it not, my good j.a.pp?"

"Ah!" said j.a.pp rather vaguely.

I smiled.

"Well," said j.a.pp, "that's the case. What do you think of it?"

"You found no clue of any kind that has not been reported?"

"Yes, there was this." j.a.pp took a small object from his pocket and handed it over to Poirot. It was a small pompon of emerald green silk, with some ragged threads hanging from it, as though it had been wrenched violently away.

"We found it in the dead man's hand, which was tightly clenched over it," explained the inspector.

Poirot handed it back without any comment and asked: "Had Lord Cronshaw any enemies?"

"None that anyone knows of. He seemed a popular young fellow."

"Who benefits by his death?"

"His uncle, the Honourable Eustace Beltane, comes into the t.i.tle and estates. There are one or two suspicious facts against him. Several people declare that they heard a violent altercation going on in the little supper room, and that Eustace Beltane was one of the disputants. You see, the table-knife being s.n.a.t.c.hed up off the table would fit in with the murder being done in the heat of a quarrel."

"What does Mr. Beltane say about the matter?"

"Declares one of the waiters was the worse for liquor, and that he was giving him a dressing down. Also that it was nearer to one than half past. You see, Captain Digby's evidence fixes the time pretty accurately. Only about ten minutes elapsed between his speaking to Cronshaw and the finding of the body."

"And in any case I suppose Mr. Beltane, as Punchinello, was wearing a hump and a ruffle?"

"I don't know the exact details of the costumes," said j.a.pp, looking curiously at Poirot. "And anyway, I don't quite see what that has got to do with it?"

"No?" There was a hint of mockery in Poirot's smile. He continued quietly, his eyes shining with the green light I had learned to recognize so well: "There was a curtain in this little supper room, was there not?"

"Yes, but-"

"With a s.p.a.ce behind it sufficient to conceal a man?"

"Yes-in fact, there's a small recess, but how you knew about it-you haven't been to the place, have you, Monsieur Poirot?"

"No, my good j.a.pp, I supplied the curtain from my brain. Without it, the drama is not reasonable. And always one must be reasonable. But tell me, did they not send for a doctor?"

"At once, of course. But there was nothing to be done. Death must have been instantaneous."

Poirot nodded rather impatiently.

"Yes, yes, I understand. This doctor, now, he gave evidence at the inquest?"

"Yes."

"Did he say nothing of any unusual symptom-was there nothing about the appearance of the body which struck him as being abnormal?"

j.a.pp stared hard at the little man.

"Yes, Monsieur Poirot. I don't know what you're getting at, but he did mention that there was a tension and stiffness about the limbs which he was quite at a loss to account for."

"Aha!" said Poirot. "Aha! Mon Dieu! j.a.pp, that gives one to think, does it not?"

I saw that it had certainly not given j.a.pp to think.

"If you're thinking of poison, monsieur, who on earth would poison a man first and then stick a knife into him?"

"In truth that would be ridiculous," agreed Poirot placidly.

"Now is there anything you want to see, monsieur? If you'd like to examine the room where the body was found-"

Poirot waved his hand.

"Not in the least. You have told me the only thing that interests me-Lord Cronshaw's views on the subject of drug taking."

"Then there's nothing you want to see?"

"Just one thing."

"What is that?"

"The set of china figures from which the costumes were copied."

j.a.pp stared.

"Well, you're a funny one!"

"You can manage that for me?"

"Come round to Berkeley Square now if you like. Mr. Beltane-or His Lordship, as I should say now-won't object."

II.

We set off at once in a taxi. The new Lord Cronshaw was not at home, but at j.a.pp's request we were shown into the "china room," where the gems of the collection were kept. j.a.pp looked round him rather helplessly.

"I don't see how you'll ever find the ones you want, monsieur."

But Poirot had already drawn a chair in front of the mantelpiece and was hopping up upon it like a nimble robin. Above the mirror, on a small shelf to themselves, stood six china figures. Poirot examined them minutely, making a few comments to us as he did so.

"Les voil! The old Italian Comedy. Three pairs! Harlequin and Columbine, Pierrot and Pierrette-very dainty in white and green-and Punchinello and Pulcinella in mauve and yellow. Very elaborate, the costume of Punchinello-ruffles and frills, a hump, a high hat. Yes, as I thought, very elaborate."

He replaced the figures carefully, and jumped down.

j.a.pp looked unsatisfied, but as Poirot had clearly no intention of explaining anything, the detective put the best face he could upon the matter. As we were preparing to leave, the master of the house came in, and j.a.pp performed the necessary introductions.

The sixth Viscount Cronshaw was a man of about fifty, suave in manner, with a handsome, dissolute face. Evidently an elderly roue, with the languid manner of a poseur. I took an instant dislike to him. He greeted us graciously enough, declaring he had heard great accounts of Poirot's skill, and placing himself at our disposal in every way.

"The police are doing all they can, I know," Poirot said.

"But I much fear the mystery of my nephew's death will never be cleared up. The whole thing seems utterly mysterious."

Poirot was watching him keenly. "Your nephew had no enemies that you know of?"

"None whatever. I am sure of that." He paused, and then went on: "If there are any questions you would like to ask-"

"Only one." Poirot's voice was serious. "The costumes-they were reproduced exactly from your figurines?"

"To the smallest detail."

"Thank you, milor'. That is all I wanted to be sure of. I wish you good day."

"And what next?" inquired j.a.pp as we hurried down the street. "I've got to report at the Yard, you know."

"Bien! I will not detain you. I have one other little matter to attend to, and then-"

"Yes?"

"The case will be complete."

"What? You don't mean it! You know who killed Lord Cronshaw?"

"Parfaitement."

"Who was it? Eustace Beltane?"

"Ah, mon ami, you know my little weakness! Always I have a desire to keep the threads in my own hands up to the last minute. But have no fear. I will reveal all when the time comes. I want no credit-the affair shall be yours, on the condition that you permit me to play out the denouement my own way."

"That's fair enough," said j.a.pp. "That is, if the denouement ever comes! But I say, you are an oyster, aren't you?" Poirot smiled. "Well, so long. I'm off to the Yard."

He strode off down the steet, and Poirot hailed a pa.s.sing taxi.

"Where are we going now?" I asked in lively curiosity.

"To Chelsea to see the Davidsons."

He gave the address to the driver.

"What do you think of the new Lord Cronshaw?" I asked.

"What says my good friend Hastings?"

"I distrust him instinctively."

"You think he is the 'wicked uncle' of the storybooks, eh?"

"Don't you?"

"Me, I think he was most amiable towards us," said Poirot noncommittally.

"Because he had his reasons!"

Poirot looked at me, shook his head sadly, and murmured something that sounded like: "No method."

III.

The Davidsons lived on the third floor of a block of "mansion" flats. Mr. Davidson was out, we were told, but Mrs. Davidson was at home. We were ushered into a long, low room with garish Oriental hangings. The air felt close and oppressive, and there was an overpowering fragrance of joss sticks. Mrs. Davidson came to us almost immediately, a small, fair creature whose fragility would have seemed pathetic and appealing had it not been for the rather shrewd and calculating gleam in her light blue eyes.

Poirot explained our connection with the case, and she shook her head sadly.

"Poor Cronch-and poor Coco too! We were both so fond of her, and her death has been a terrible grief to us. What is it you want to ask me? Must I really go over all that dreadful evening again?"

"Oh, madame, believe me, I would not hara.s.s your feelings unnecessarily. Indeed, Inspector j.a.pp has told me all that is needful. I only wish to see the costume you wore at the ball that night."

The lady looked somewhat surprised, and Poirot continued smoothly: "You comprehend, madame, that I work on the system of my country. There we always 'reconstruct' the crime. It is possible that I may have an actual representation, and if so, you understand, the costumes would be important."