"Poirot, you old villain," I said, "I've half a mind to strangle you! What do you mean by deceiving me as you have done?"

We were sitting in the library. Several hectic days lay behind us. In the room below, John and Mary were together once more, while Alfred Inglethorp and Miss Howard were in custody. Now at last, I had Poirot to myself, and could relieve my still burning curiosity.

Poirot did not answer me for a moment, but at last he said:

"I did not deceive you, mon ami. At most, I permitted you to deceive yourself."

"Yes, but why?"

"Well, it is difficult to explain. You see, my friend, you have a nature so honest, and a countenance so transparent, that— enfin, to conceal your feelings is impossible! If I had told you my ideas, the very first time you saw Mr. Alfred Inglethorp that astute gentleman would have—in your so expressive idiom—'smelt a rat'! And then, bonjour to our chances of catching him!"

"I think that I have more diplomacy than you give me credit for."

"My friend," besought Poirot, "I implore you, do not enrage yourself! Your help has been of the most invaluable. It is but the extremely beautiful nature that you have, which made me pause."

"Well," I grumbled, a little mollified. "I still think you might have given me a hint."

"But I did, my friend. Several hints. You would not take them. Think now, did I ever say to you that I believed John Cavendish guilty? Did I not, on the contrary, tell you that he would almost certainly be acquitted?"

"Yes, but——"

"And did I not immediately afterwards speak of the difficulty of bringing the murderer to justice? Was it not plain to you that I was speaking of two entirely different persons?"

"No," I said, "it was not plain to me!"

"Then again," continued Poirot, "at the beginning, did I not repeat to you several times that I didn't want Mr. Inglethorp arrested now? That should have conveyed something to you."

"Do you mean to say you suspected him as long ago as that?"

"Yes. To begin with, whoever else might benefit by Mrs. Inglethorp's death, her husband would benefit the most. There was no getting away from that. When I went up to Styles with you that first day, I had no idea as to how the crime had been committed, but from what I knew of Mr. Inglethorp I fancied that it would be very hard to find anything to connect him with it. When I arrived at the chateau, I realized at once that it was Mrs. Inglethorp who had burnt the will; and there, by the way, you cannot complain, my friend, for I tried my best to force on you the significance of that bedroom fire in midsummer."

"Yes, yes," I said impatiently. "Go on."

"Well, my friend, as I say, my views as to Mr. Inglethorp's guilt were very much shaken. There was, in fact, so much evidence against him that I was inclined to believe that he had not done it."

"When did you change your mind?"

"When I found that the more efforts I made to clear him, the more efforts he made to get himself arrested. Then, when I discovered that Inglethorp had nothing to do with Mrs. Raikes and that in fact it was John Cavendish who was interested in that quarter, I was quite sure."

"But why?"

"Simply this. If it had been Inglethorp who was carrying on an intrigue with Mrs. Raikes, his silence was perfectly comprehensible. But, when I discovered that it was known all over the village that it was John who was attracted by the farmer's pretty wife, his silence bore quite a different interpretation. It was nonsense to pretend that he was afraid of the scandal, as no possible scandal could attach to him. This attitude of his gave me furiously to think, and I was slowly forced to the conclusion that Alfred Inglethorp wanted to be arrested. Eh bien!from that moment, I was equally determined that he should not be arrested."

"Wait a minute. I don't see why he wished to be arrested?"

"Because, mon ami, it is the law of your country that a man once acquitted can never be tried again for the same offence. Aha! but it was clever—his idea! Assuredly, he is a man of method. See here, he knew that in his position he was bound to be suspected, so he conceived the exceedingly clever idea of preparing a lot of manufactured evidence against himself. He wished to be arrested. He would then produce his irreproachable alibi—and, hey presto, he was safe for life!"

"But I still don't see how he managed to prove his alibi, and yet go to the chemist's shop?"

Poirot stared at me in surprise.

"Is it possible? My poor friend! You have not yet realized that it was Miss Howard who went to the chemist's shop?"

"Miss Howard?"

"But, certainly. Who else? It was most easy for her. She is of a good height, her voice is deep and manly; moreover, remember, she and Inglethorp are cousins, and there is a distinct resemblance between them, especially in their gait and bearing. It was simplicity itself. They are a clever pair!"

"I am still a little fogged as to how exactly the bromide business was done," I remarked.

"Bon! I will reconstruct for you as far as possible. I am inclined to think that Miss Howard was the master mind in that affair. You remember her once mentioning that her father was a doctor? Possibly she dispensed his medicines for him, or she may have taken the idea from one of the many books lying about when Mademoiselle Cynthia was studying for her exam. Anyway, she was familiar with the fact that the addition of a bromide to a mixture containing strychnine would cause the precipitation of the latter. Probably the idea came to her quite suddenly. Mrs. Inglethorp had a box of bromide powders, which she occasionally took at night. What could be easier than quietly to dissolve one or more of those powders in Mrs. Inglethorp's large sized bottle of medicine when it came from Coot's? The risk is practically nil. The tragedy will not take place until nearly a fortnight later. If anyone has seen either of them touching the medicine, they will have forgotten it by that time. Miss Howard will have engineered her quarrel, and departed from the house. The lapse of time, and her absence, will defeat all suspicion. Yes, it was a clever idea! If they had left it alone, it is possible the crime might never have been brought home to them. But they were not satisfied. They tried to be too clever—and that was their undoing."

Poirot puffed at his tiny cigarette, his eyes fixed on the ceiling.

"They arranged a plan to throw suspicion on John Cavendish, by buying strychnine at the village chemist's, and signing the register in his hand-writing.

"On Monday Mrs. Inglethorp will take the last dose of her medicine. On Monday, therefore, at six o'clock, Alfred Inglethorp arranges to be seen by a number of people at a spot far removed from the village. Miss Howard has previously made up a cock and bull story about him and Mrs. Raikes to account for his holding his tongue afterwards. At six o'clock, Miss Howard, disguised as Alfred Inglethorp, enters the chemist's shop, with her story about a dog, obtains the strychnine, and writes the name of Alfred Inglethorp in John's handwriting, which she had previously studied carefully.

"But, as it will never do if John, too, can prove an alibi, she writes him an anonymous note—still copying his hand-writing—which takes him to a remote spot where it is exceedingly unlikely that anyone will see him.

"So far, all goes well. Miss Howard goes back to Middlingham. Alfred Inglethorp returns to Styles. There is nothing that can compromise him in any way, since it is Miss Howard who has the strychnine, which, after all, is only wanted as a blind to throw suspicion on John Cavendish.

"But now a hitch occurs. Mrs. Inglethorp does not take her medicine that night. The broken bell, Cynthia's absence—arranged by Inglethorp through his wife—all these are wasted. And then—he makes his slip.

"Mrs. Inglethorp is out, and he sits down to write to his accomplice, who, he fears, may be in a panic at the nonsuccess of their plan. It is probable that Mrs. Inglethorp returned earlier than he expected. Caught in the act, and somewhat flurried he hastily shuts and locks his desk. He fears that if he remains in the room he may have to open it again, and that Mrs. Inglethorp might catch sight of the letter before he could snatch it up. So he goes out and walks in the woods, little dreaming that Mrs. Inglethorp will open his desk, and discover the incriminating document.

"But this, as we know, is what happened. Mrs. Inglethorp reads it, and becomes aware of the perfidy of her husband and Evelyn Howard, though, unfortunately, the sentence about the bromides conveys no warning to her mind. She knows that she is in danger—but is ignorant of where the danger lies. She decides to say nothing to her husband, but sits down and writes to her solicitor, asking him to come on the morrow, and she also determines to destroy immediately the will which she has just made. She keeps the fatal letter."

"It was to discover that letter, then, that her husband forced the lock of the despatch-case?"

"Yes, and from the enormous risk he ran we can see how fully he realized its importance. That letter excepted, there was absolutely nothing to connect him with the crime."

"There's only one thing I can't make out, why didn't he destroy it at once when he got hold of it?"

"Because he did not dare take the biggest risk of all—that of keeping it on his own person."

"I don't understand."

"Look at it from his point of view. I have discovered that there were only five short minutes in which he could have taken it—the five minutes immediately before our own arrival on the scene, for before that time Annie was brushing the stairs, and would have seen anyone who passed going to the right wing. Figure to yourself the scene! He enters the room, unlocking the door by means of one of the other doorkeys—they were all much alike. He hurries to the despatch-case—it is locked, and the keys are nowhere to be seen. That is a terrible blow to him, for it means that his presence in the room cannot be concealed as he had hoped. But he sees clearly that everything must be risked for the sake of that damning piece of evidence. Quickly, he forces the lock with a penknife, and turns over the papers until he finds what he is looking for.

"But now a fresh dilemma arises: he dare not keep that piece of paper on him. He may be seen leaving the room—he may be searched. If the paper is found on him, it is certain doom. Probably, at this minute, too, he hears the sounds below of Mr. Wells and John leaving the boudoir. He must act quickly. Where can he hide this terrible slip of paper? The contents of the waste-paper-basket are kept and in any case, are sure to be examined. There are no means of destroying it; and he dare not keep it. He looks round, and he sees—what do you think,mon ami?"

I shook my head.

"In a moment, he has torn the letter into long thin strips, and rolling them up into spills he thrusts them hurriedly in amongst the other spills in the vase on the mantle-piece."

I uttered an exclamation.

"No one would think of looking there," Poirot continued. "And he will be able, at his leisure, to come back and destroy this solitary piece of evidence against him."

"Then, all the time, it was in the spill vase in Mrs. Inglethorp's bedroom, under our very noses?" I cried.

Poirot nodded.

"Yes, my friend. That is where I discovered my 'last link,' and I owe that very fortunate discovery to you."

"To me?"

"Yes. Do you remember telling me that my hand shook as I was straightening the ornaments on the mantel-piece?"

"Yes, but I don't see——"

"No, but I saw. Do you know, my friend, I remembered that earlier in the morning, when we had been there together, I had straightened all the objects on the mantel-piece. And, if they were already straightened, there would be no need to straighten them again, unless, in the meantime, someone else had touched them."

"Dear me," I murmured, "so that is the explanation of your extraordinary behaviour. You rushed down to Styles, and found it still there?"

"Yes, and it was a race for time."

"But I still can't understand why Inglethorp was such a fool as to leave it there when he had plenty of opportunity to destroy it."

"Ah, but he had no opportunity. I saw to that."

"You?"

"Yes. Do you remember reproving me for taking the household into my confidence on the subject?"

"Yes."

"Well, my friend, I saw there was just one chance. I was not sure then if Inglethorp was the criminal or not, but if he was I reasoned that he would not have the paper on him, but would have hidden it somewhere, and by enlisting the sympathy of the household I could effectually prevent his destroying it. He was already under suspicion, and by making the matter public I secured the services of about ten amateur detectives, who would be watching him unceasingly, and being himself aware of their watchfulness he would not dare seek further to destroy the document. He was therefore forced to depart from the house, leaving it in the spill vase."

"But surely Miss Howard had ample opportunities of aiding him."

"Yes, but Miss Howard did not know of the paper's existence. In accordance with their prearranged plan, she never spoke to Alfred Inglethorp. They were supposed to be deadly enemies, and until John Cavendish was safely convicted they neither of them dared risk a meeting. Of course I had a watch kept on Mr. Inglethorp, hoping that sooner or later he would lead me to the hiding-place. But he was too clever to take any chances. The paper was safe where it was; since no one had thought of looking there in the first week, it was not likely they would do so afterwards. But for your lucky remark, we might never have been able to bring him to justice."

"I understand that now; but when did you first begin to suspect Miss Howard?"

"When I discovered that she had told a lie at the inquest about the letter she had received from Mrs. Inglethorp."

"Why, what was there to lie about?"

"You saw that letter? Do you recall its general appearance?"

"Yes—more or less."

"You will recollect, then, that Mrs. Inglethorp wrote a very distinctive hand, and left large clear spaces between her words. But if you look at the date at the top of the letter you will notice that 'July 17th' is quite different in this respect. Do you see what I mean?"

"No," I confessed, "I don't."

"You do not see that that letter was not written on the 17th, but on the 7th—the day after Miss Howard's departure? The '1' was written in before the '7' to turn it into the '17th'."

"But why?"

"That is exactly what I asked myself. Why does Miss Howard suppress the letter written on the 17th, and produce this faked one instead? Because she did not wish to show the letter of the 17th. Why, again? And at once a suspicion dawned in my mind. You will remember my saying that it was wise to beware of people who were not telling you the truth."

"And yet," I cried indignantly, "after that, you gave me two reasons why Miss Howard could not have committed the crime!"

"And very good reasons too," replied Poirot. "For a long time they were a stumbling-block to me until I remembered a very significant fact: that she and Alfred Inglethorp were cousins. She could not have committed the crime single-handed, but the reasons against that did not debar her from being an accomplice. And, then, there was that rather over-vehement hatred of hers! It concealed a very opposite emotion. There was, undoubtedly, a tie of passion between them long before he came to Styles. They had already arranged their infamous plot—that he should marry this rich, but rather foolish old lady, induce her to make a will leaving her money to him, and then gain their ends by a very cleverly conceived crime. If all had gone as they planned, they would probably have left England, and lived together on their poor victim's money.

"They are a very astute and unscrupulous pair. While suspicion was to be directed against him, she would be making quiet preparations for a very different dénouement. She arrives from Middlingham with all the compromising items in her possession. No suspicion attaches to her. No notice is paid to her coming and going in the house. She hides the strychnine and glasses in John's room. She puts the beard in the attic. She will see to it that sooner or later they are duly discovered."

"I don't quite see why they tried to fix the blame on John," I remarked. "It would have been much easier for them to bring the crime home to Lawrence."

"Yes, but that was mere chance. All the evidence against him arose out of pure accident. It must, in fact, have been distinctly annoying to the pair of schemers."

"His manner was unfortunate," I observed thoughtfully.

"Yes. You realize, of course, what was at the back of that?"

"No."

"You did not understand that he believed Mademoiselle Cynthia guilty of the crime?"

"No," I exclaimed, astonished. "Impossible!"

"Not at all. I myself nearly had the same idea. It was in my mind when I asked Mr. Wells that first question about the will. Then there were the bromide powders which she had made up, and her clever male impersonations, as Dorcas recounted them to us. There was really more evidence against her than anyone else."

"You are joking, Poirot!"

"No. Shall I tell you what made Monsieur Lawrence turn so pale when he first entered his mother's room on the fatal night? It was because, whilst his mother lay there, obviously poisoned, he saw, over your shoulder, that the door into Mademoiselle Cynthia's room was unbolted."

"But he declared that he saw it bolted!" I cried.

"Exactly," said Poirot dryly. "And that was just what confirmed my suspicion that it was not. He was shielding Mademoiselle Cynthia."

"But why should he shield her?"

"Because he is in love with her."

I laughed.

"There, Poirot, you are quite wrong! I happen to know for a fact that, far from being in love with her, he positively dislikes her."

"Who told you that, mon ami?"

"Cynthia herself."

"La pauvre petite! And she was concerned?"

"She said that she did not mind at all."

"Then she certainly did mind very much," remarked Poirot. "They are like that—les femmes!"

"What you say about Lawrence is a great surprise to me," I said.

"But why? It was most obvious. Did not Monsieur Lawrence make the sour face every time Mademoiselle Cynthia spoke and laughed with his brother? He had taken it into his long head that Mademoiselle Cynthia was in love with Monsieur John. When he entered his mother's room, and saw her obviously poisoned, he jumped to the conclusion that Mademoiselle Cynthia knew something about the matter. He was nearly driven desperate. First he crushed the coffee-cup to powder under his feet, remembering that she had gone up with his mother the night before, and he determined that there should be no chance of testing its contents. Thenceforward, he strenuously, and quite uselessly, upheld the theory of 'Death from natural causes'."

"And what about the 'extra coffee-cup'?"

"I was fairly certain that it was Mrs. Cavendish who had hidden it, but I had to make sure. Monsieur Lawrence did not know at all what I meant; but, on reflection, he came to the conclusion that if he could find an extra coffee-cup anywhere his lady love would be cleared of suspicion. And he was perfectly right."

"One thing more. What did Mrs. Inglethorp mean by her dying words?"

"They were, of course, an accusation against her husband."

"Dear me, Poirot," I said with a sigh, "I think you have explained everything. I am glad it has all ended so happily. Even John and his wife are reconciled."

"Thanks to me."

"How do you mean—thanks to you?"

"My dear friend, do you not realize that it was simply and solely the trial which has brought them together again? That John Cavendish still loved his wife, I was convinced. Also, that she was equally in love with him. But they had drifted very far apart. It all arose from a misunderstanding. She married him without love. He knew it. He is a sensitive man in his way, he would not force himself upon her if she did not want him. And, as he withdrew, her love awoke. But they are both unusually proud, and their pride held them inexorably apart. He drifted into an entanglement with Mrs. Raikes, and she deliberately cultivated the friendship of Dr. Bauerstein. Do you remember the day of John Cavendish's arrest, when you found me deliberating over a big decision?"

"Yes, I quite understood your distress."

"Pardon me, mon ami, but you did not understand it in the least. I was trying to decide whether or not I would clear John Cavendish at once. I could have cleared him—though it might have meant a failure to convict the real criminals. They were entirely in the dark as to my real attitude up to the very last moment—which partly accounts for my success."

"Do you mean that you could have saved John Cavendish from being brought to trial?"

"Yes, my friend. But I eventually decided in favour of 'a woman's happiness'. Nothing but the great danger through which they have passed could have brought these two proud souls together again."

I looked at Poirot in silent amazement. The colossal cheek of the little man! Who on earth but Poirot would have thought of a trial for murder as a restorer of conjugal happiness!

"I perceive your thoughts, mon ami," said Poirot, smiling at me. "No one but Hercule Poirot would have attempted such a thing! And you are wrong in condemning it. The happiness of one man and one woman is the greatest thing in all the world."

His words took me back to earlier events. I remembered Mary as she lay white and exhausted on the sofa, listening, listening. There had come the sound of the bell below. She had started up. Poirot had opened the door, and meeting her agonized eyes had nodded gently. "Yes, madame," he said. "I have brought him back to you." He had stood aside, and as I went out I had seen the look in Mary's eyes, as John Cavendish had caught his wife in his arms.

"Perhaps you are right, Poirot," I said gently. "Yes, it is the greatest thing in the world."

Suddenly, there was a tap at the door, and Cynthia peeped in.

"I—I only——"

"Come in," I said, springing up.

She came in, but did not sit down.

"I—only wanted to tell you something——"

"Yes?"

Cynthia fidgeted with a little tassel for some moments, then, suddenly exclaiming: "You dears!" kissed first me and then Poirot, and rushed out of the room again.

"What on earth does this mean?" I asked, surprised.

It was very nice to be kissed by Cynthia, but the publicity of the salute rather impaired the pleasure.

"It means that she has discovered Monsieur Lawrence does not dislike her as much as she thought," replied Poirot philosophically.

"But——"

"Here he is."

Lawrence at that moment passed the door.

"Eh! Monsieur Lawrence," called Poirot. "We must congratulate you, is it not so?"

Lawrence blushed, and then smiled awkwardly. A man in love is a sorry spectacle. Now Cynthia had looked charming.

I sighed.

"What is it, mon ami?"

"Nothing," I said sadly. "They are two delightful women!"

"And neither of them is for you?" finished Poirot. "Never mind. Console yourself, my friend. We may hunt together again, who knows? And then——"

THE END