The Mystery of the Blue Train

Poirot alone seemed unconscious of the sense of strain, and chatted pleasantly in a laudable attempt to put every one at their ease. He paid little compliments.

"It is amazing, M. Kettering, how well you speak the French," he observed-"so well that you could be taken for a Frenchman if you chose. That is a very rare accomplishment among Englishmen."

"I wish I did," said Katherine. "I am only too well aware that my French is of a painfully British order."

They reached their seats and sat down, and almost immediately Knighton perceived his employer signalling to him from the other end of the court, and went off to speak to him.

"Me, I approve of that young man," said Poirot, sending a beaming smile after the departing secretary, "and you. Mademoiselle?"

"I like him very much."

"And you, M. Kettering?"

Some quick rejoinder was springing to Derek's lips, but he checked it as though something in the little Belgian's twinkling eyes had made him suddenly alert. He spoke carefully, choosing his words.

"Knighton is a very good fellow," he said- Just for a moment Katherine fancied that Poirot looked disappointed.

"He is a great admirer of yours, M. Poirot," she said, and she related some of the things that Knighton had said. It amused her to see the little man plume himself like a bird, thrusting out his chest, and assuming an air of mock modesty that would have deceived no one.

"That reminds me. Mademoiselle," he said suddenly, "I have a little matter of business I have to speak to you about. When you were sitting talking to that poor lady in the train, I think you must have dropped a cigarette case."

Katherine looked rather astonished. "I don't think so," she said. Poirot drew from his pocket a cigarette case of soft blue leather, with the initial "K" on it in gold.

"No, that is not mine," Katherine said.

"Ah, a thousand apologies. It was doubtless Madame's own. 'K', of course, stands for Kettering. We were doubtful, because she had another cigarette case in her bag, and it seemed odd that she should have two."

He turned to Derek suddenly. "You do not know, I suppose, whether this was your wife's case or not?"

Derek seemed momentarily taken aback. He stammered a little in his reply: "I-I don't know. I suppose so."

"It is not yours by any chance?"

"Certainly not. If it were mine it would hardly have been in my wife's possession."

Poirot looked more ingenuous and childlike than ever.

"I thought perhaps you might have dropped it when you were in your wife's compartment," he explained guilelessly.

"I never was there. I have already told the police that a dozen times."

"A thousand pardons," said Poirot, with his most apologetic air. "It was Mademoiselle here who mentioned having seen you going in."

He stopped with an air of embarrassment.

Katherine looked at Derek. His face had gone rather white, but perhaps that was her fancy. His laugh, when it came, was natural enough.

"You made a mistake. Miss Grey," he said easily. "From what the police have told me, I gather that my own compartment was only a door or two away from that of my wife's -though I never suspected the fact at the time. You must have seen me going into my own compartment." He got up quickly as he saw Van Aldin and Knighton approaching.

"I'm going to leave you now," he an' nounced. "I can't stand my father-in-law at any price..

Van Aldin greeted Kathenne very courteously, but was clearly in a bad humour.

"You seem fond of watching tennis, M. Poirot," he growled.

"It is a pleasure to me, yes," cried Poirot placidly.

"It is as well you are in France," said Van Aldin. "We are made of sterner stuff in the States. Business comes before pleasure there."

Poirot did not take offence; indeed, he smiled gently and confidingly at the irate millionaire.

"Do not enrage yourself, I beg of you.

Every one his own methods. Me, I have always found it a delightful and pleasing idea to combine business and pleasure together."

He glanced at the other two. They were deep in conversation, absorbed in each other. Poirot nodded his head in satisfaction, and then leant towards the millionaire, lowing his voice as he did so.

"It is not only for pleasure that I am here, M. Van Aldin. Observe just opposite us that the old man-the one with the yellow face and the venerable beard." "Well, what of him?"

"That," Poirot said, "is M. Papopolous" "A Greek, eh?"

"As you say-a Greek. He is a dealer in antiques of world-wide reputation. He has a small shop in Paris, and he is suspected by the police of being something more."

"What?"

"A receiver of stolen goods, especially jewels. There is nothing as to the re-cutting and re-setting of gems that he does not know.

He deals with the highest in Europe and with the lowest of the riff-raff of the underworld."

Van Aldin was looking at Poirot with suddenly awakened attention.

"Well?" he demanded, a new note in his voice.

"I ask myself," said Poirot, "I, Hercule Poirot"-he thumped himself dramatically on the chest-"ask myself why is M. Papopolous suddenly come to Nice?"