“Upon my soul, I don’t know,” he said at last. “I have always had and still have the utmost belief in M. Poirot, but—well, this takes a bit of believing.”
“This Li Chang Yen, too,” continued M. Desjardeaux. “Who has ever heard of him?”
“I have,” said the unexpected voice of Mr. Ingles.
The Frenchman stared at him, and he stared placidly back again, looking more like a Chinese idol than ever. “Mr. Ingles,” explained the Home Secretary, “is the greatest authority we have on the interior of China.”
“And you have heard of this Li Chang Yen?”
“Until M. Poirot here came to me, I imagined that I was the only man in England who had. Make no mistake, M. Desjardeaux, there is only one man in China who counts today—Li Chang Yen. He has, perhaps, I only say perhaps, the finest brain in the world at the present time.”
M. Desjardeaux sat as though stunned. Presently, however, he rallied.
“There may be something in what you say, M. Poirot,” he said coldly. “But as regards Madame Olivier, you are most certainly mistaken. She is a true daughter of France, and devoted solely to the cause of science.”
Poirot shrugged his shoulders and did not answer.
There was a minute or two’s pause, and then my little friend rose to his feet, with an air of dignity that sat rather oddly upon his quaint personality.
“That is all I have to say, messieurs—to warn you. I thought it likely that I should not be believed. But at least you will be on your guard. My words will sink in, and each fresh event that comes along will confirm your wavering faith. It was necessary for me to speak now—later I might not have been able to do so.”
“You mean—?” asked Crowther, impressed in spite of himself by the gravity of Poirot’s tone.
“I mean, monsieur, that since I have penetrated the identity of Number Four, my life is not worth an hour’s purchase. He will seek to destroy me at all costs—and not for nothing is he named ‘The Destroyer.’ Messieurs, I salute you. To you, M. Crowther, I deliver this key, and this sealed envelope. I have got together all my notes on the case, and my ideas as to how best to meet the menace that any day may break upon the world, and have placed them in a certain safe deposit. In the event of my death, M. Crowther, I authorize you to take charge of those papers and make what use you can of them. And now, messieurs, I wish you good day.”
Desjardeaux merely bowed coldly, but Crowther sprang up and held out his hand.
“You have converted me, M. Poirot. Fantastic as the whole thing seems, I believe utterly in the truth of what you have told us.”
Ingles left at the same time as we did.
“I am not disappointed with the interview,” said Poirot, as we walked along. “I did not expect to convince Desjardeaux, but I have at least ensured that, if I die, my knowledge does not die with me. And I have made one or two converts. Pas si mal!”
“I’m with you, as you know,” said Ingles. “By the way, I’m going out to China as soon as I can get off.”
“Is that wise?”
“No,” said Ingles drily. “But it’s necessary. One must do what one can.”
“Ah, you are a brave man!” cried Poirot with emotion. “If we were not in the street, I would embrace you.”
I fancied that Ingles looked rather relieved.
“I don’t suppose that I shall be in any more danger in China than you are in London,” he growled.
“That is possibly true enough,” admitted Poirot. “I hope that they will not succeed in massacring Hastings also, that is all. That would annoy me greatly.”
I interrupted this cheerful conversation to remark that I had no intention of letting myself be massacred, and shortly afterwards Ingles parted from us.
For some time we went along in silence, which Poirot at length broke by uttering a totally unexpected remark.
“I think—I really think—that I shall have to bring my brother into this.”
“Your brother,” I cried, astonished. “I never knew you had a brother?”
“You surprise me, Hastings. Do you not know that all celebrated detectives have brothers who would be even more celebrated than they are were it not for constitutional indolence?”
Poirot employs a peculiar manner sometimes which makes it well-nigh impossible to know whether he is jesting or in earnest. That manner was very evident at the moment.
“What is your brother’s name?” I asked, trying to adjust myself to this new idea.
“Achille Poirot,” replied Poirot gravely. “He lives near Spa in Belgium.”
“What does he do?” I asked with some curiosity, putting aside a half-formed wonder as to the character and disposition of the late Madame Poirot, and her classical taste in Christian names.
“He does nothing. He is, as I tell, of a singularly indolent disposition. But his abilities are hardly less than my own—which is saying a great deal.”
“Is he like you to look at?”
“Not unlike. But not nearly so handsome. And he wears no moustaches.”
“Is he older than you, or younger?”
“He happens to have been born on the same day.”
“A twin,” I cried.
“Exactly, Hastings. You jump to the right conclusion with unfailing accuracy. But here we are at home again. Let us at once get to work on that little affair of the Duchess’s necklace.”
But the Duchess’s necklace was doomed to wait awhile. A case of quite another description was waiting for us.
Our landlady, Mrs. Pearson, at once informed us that a hospital nurse had called and was waiting to see Poirot.
We found her sitting in the big armchair facing the window, a pleasant-faced woman of middle age, in a dark blue uniform. She was a little reluctant to come to the point, but Poirot soon put her at her ease, and she embarked upon her story.
“You see, M. Poirot, I’ve never come across anything of the kind before. I was sent for, from the Lark Sisterhood, to go down to a case in Hertfordshire. An
