“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 denouement. 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