The next moment Poirot embraced me warmly. “Enfin! You have arrived. And all by yourself. It is superb! Continue your reasoning. You are right. Decidedly we have done wrong to forget Georges Conneau.”  
I was so flattered by the little man’s approval that I could hardly continue. But at last I collected my thoughts and went on.
 
“Georges Conneau disappeared twenty years ago, but we have no reason to believe that he is dead.”
 
“Aucunement,” agreed Poirot. “Proceed.”
 
“Therefore we will assume that he is alive.”
 
“Exactly.”
 
“Or that he was alive until recently.”
 
“De mieux en mieux!”
 
“We will presume,” I continued, my enthusiasm rising, “that he has fallen on evil days. He has become a criminal, an apache, a tramp—a what you will. He chances to come to Merlinville. There he finds the woman he has never ceased to love.”
 
“Eh eh! The sentimentality,” warned Poirot.
 
“Where one hates one also loves,” I quoted or misquoted. “At any rate he finds her there, living under an assumed name. But she has a new lover, the Englishman, Renauld. Georges Conneau, the memory of old wrongs rising in him, quarrels with this Renauld. He lies in wait for him as he comes to visit his mistress, and stabs him in the back. Then, terrified at what he has done, he starts to dig a grave. I imagine it likely that Madame Daubreuil comes out to look for her lover. She and Conneau have a terrible scene. He drags her into the shed, and there suddenly falls down in an epileptic fit. Now supposing Renauld to appear. Madame Daubreuil tells him all, points out to him the dreadful consequences to her daughter if this scandal of the past is revived. His father’s murderer is dead—let them do their best to it up. Jack Renauld consents—goes to the house and has an interview with his mother, winning her over to his point of view. Primed with the story that Madame Daubreuil has suggested to him, she permits herself to be gagged and bound. There, Poirot, what do you think of that?” I leaned back, flushed with the pride of successful .
 
Poirot looked at me thoughtfully.
 
“I think that you should write for the Kinema, mon ami,” he remarked at last.
 
“You mean—?”
 
“It would make a good film, the story that you have recounted to me there—but it bears no sort of resemblance to everyday life.”
 
“I admit that I haven’t gone into all the details, but—”
 
“You have gone further—you have ignored them magnificently. What about the way the two men were dressed? Do you suggest that after stabbing his victim, Conneau removed his suit of clothes, donned it himself, and replaced the ?”
 
“I don’t see that that matters,” I objected rather huffily. “He may have obtained clothes and money from Madame Daubreuil by threats earlier in the day.”
 
“By threats—eh? You seriously advance that supposition?”
 
“Certainly. He could have threatened to reveal her identity to the Renaulds, which would probably have put an end to all hopes of her daughter’s marriage.”
 
“You are wrong, Hastings. He could not her, for she had the whip hand. Georges Conneau, remember, is still wanted for murder. A word from her and he is in danger of the guillotine.”
 
I was forced, rather reluctantly, to admit the truth of this.
 
“Your theory,” I remarked acidly, “is doubtless correct as to all the details?”
 
“My theory is the truth,” said Poirot quietly. “And the truth is necessarily correct. In your theory you made a fundamental error. You permitted your imagination to lead you astray with midnight assignations and love scenes. But in investigating crime we must take our stand upon the commonplace. Shall I demonstrate my methods to you?”
 
“Oh, by all means let us have a !”
 
Poirot sat very upright and began, wagging his emphatically to emphasize his points.
 
“I will start as you started from the basic fact of Georges Conneau. Now the story told by Madame Beroldy in court as to the ‘Russians’ was admittedly a fabrication. If she was innocent of in the crime, it was by her, and by her only as she stated. If, on the other hand, she was not innocent, it might have been invented by either her or Georges Conneau.
 
“Now in this case we are investigating, we meet the same tale. As I out to you, the facts render it very unlikely that Madame Daubreuil inspired it. So we turn to the hypothesis that the story had its origin in the brain of Georges Conneau. Very good. Georges Conneau, therefore, planned the crime with Madame Renauld as his . She is in the limelight, and behind her is a shadowy figure whose is unknown to us.
 
“Now let us go carefully over the Renauld Case from the beginning, setting down each significant point in its order. You have a notebook and pencil? Good. Now what is the earliest point to note down?”
 
“The letter to you?”
 
“That was the first we knew of it, but it is not the proper beginning of the case. The first point of any significance, I should say, is the change that came over M. Renauld shortly after arriving in Merlinville, and which is to by several witnesses. We have also to consider his friendship with Madame Daubreuil, and the large sums of money paid over to her. From thence we can come directly to the 23rd May.”
 
Poirot paused, cleared his throat, and signed to me to write.
 
“23rd May. M. Renauld quarrels with his son over latter’s wish to marry Marthe Daubreuil. Son leaves for Paris.
 
“24th May. M. Renauld alters his will, leaving entire control of his fortune in his wife’s hands.
 
“7th June. Quarrel with tramp in garden, witnessed by Marthe Daubreuil.
 
“Letter written to M. Hercule Poirot, assistance.
 
“Telegram sent to Jack Renauld, bidding him proceed by the Anzora to Buenos Ayres.
 
“, Masters, sent off on a holiday.
 
“Visit of a lady, that evening. As he is seeing her out, his words are ‘Yes, yes—but for God’s sake go now. …’ ”
 
Poirot paused.
 
“There, Hastings, take each of those facts one by one, consider them carefully by themselves and in relation to the whole, and see if you do not get new light on the matter.”
 
I endeavoured to do as he had said. After a moment or two, I said rather doubtfully:
 
“As to the first points, the question seems to be whether we adopt the theory of blackmail, or of an infatuation for this woman.”
 
“Blackmail, decidedly. You heard what Stonor said as to his character and habits.”
 
“Mrs. Renauld did not confirm his view,” I argued.
 
“We have already seen that Madame Renauld’s cannot be relied upon in any way. We must trust to Stonor on that point.”
 
“Still, if Renauld had an affair with a woman called Bella, there seems no inherent improbability in his having another with Madame Daubreuil.”
 
“None whatever, I grant you, Hastings. But did he?”
 
“The letter, Poirot. You forget the letter.”
 
“No, I do not forget. But what makes you think that letter was written to M. Renauld?”
 
“Why it was found in his pocket and—and—”
 
“And that is all!” cut in Poirot. “There was no mention of any name to show to whom the letter was addressed. We assumed it was to the dead man because it was in the pocket of his overcoat. Now, mon ami, something about that overcoat struck me as unusual. I measured it, and made the remark that he wore his overcoat very long. That remark should have given you to think.”
 
“I thought you were just saying it for the sake of saying something,” I confessed.
 
“Ah, quelle idée! Later you observed me measuring the overcoat of M. Jack Renauld. Eh bien, M. Jack Renauld wears his overcoat very short. Put those two facts together with a third, namely that M. Jack Renauld flung out of the house in a hurry on his departure for Paris, and tell me what you make of it!”
 
“I see,” I said slowly, as the meaning of Poirot’s remarks bore in upon me. “That letter was written to Jack Renauld—not to his father. He caught up the wrong overcoat in his haste and .”
 
Poirot nodded.
 
“Précisement! We can return to this point later. For............