“I don’t understand you, Mademoiselle.”

“I think you understand me very well.” She smiled. “You wanted to get me alone. Wasn’t that it?”

“You are putting words into my mouth, Mademoiselle.”

“And ideas into your head? No, I don’t think so. The ideas are already there. That is right, isn’t it?”

“Mademoiselle, we have a proverb–”

“Qui s’excuse s’accuse – is that what you were going to say? You must give me the credit for a certain amount of observation and common sense. For some reason or other you have got it into your head that I know something about this sordid business – this murder of a man I never saw before.”

“You are imagining things, Mademoiselle.”

“No, I am not imagining things at all. But it seems to me that a lot of time is wasted by not speaking the truth – by beating about the bush instead of coming straight out with things.”

“And you do not like the waste of time. No, you like to come straight to the point. You like the direct method. Eh bien, I will give it to you, the direct method. I will ask you the meaning of certain words that I overheard on the journey from Syria. I had got out of the train to do what the English call ‘stretch the legs’ at the station of Konya. Your voice and the Colonel’s, Mademoiselle, they came to me out of the night. You said to him, ‘Not now. Not now. When it’s all over. When it’s behind us.’ What did you mean by those words, Mademoiselle?”

She asked very quietly, “Do you think I meant – murder?”

“It is I who am asking you, Mademoiselle.”

She sighed – was lost a minute in thought. Then, as though rousing herself, she said:

“Those words had a meaning, Monsieur, but not one that I can tell you. I can only give you my solemn word of honour that I had never set eyes on this man Ratchett in my life until I saw him on this train.”

“And – you refuse to explain those words?”

“Yes, if you like to put it that way – I refuse. They had to do with – with a task I had undertaken.”

“A task that is now ended?”

“What do you mean?”

“It is ended, is it not?”

“Why should you think so?”

“Listen, Mademoiselle, I will recall to you another incident. There was a delay to the train on the day we were to reach Stamboul. You were very agitated, Mademoiselle. You, so calm, so self-controlled. You lost that calm.”

“I did not want to miss my connection.”

“So you said. But, Mademoiselle, the Orient Express leaves Stamboul every day of the week. Even if you had missed the connection it would only have been a matter of twenty-four hours’ delay.”

Miss Debenham for the first time showed signs of losing her temper.

“You do not seem to realise that one may have friends awaiting one’s arrival in London, and that a day’s delay upsets arrangements and causes a lot of annoyance.”

“Ah, it is like that? There are friends awaiting your arrival? You do not want to cause them inconvenience?”

“Naturally.”

“And yet – it is curious–”

“What is curious?”

“On this train – again we have a delay. And this time a more serious delay, since there is no possibility of sending a telegram to your friends or of getting them on the long – the long–”

“Long distance? The telephone, you mean.”

“Ah, yes, the portmanteau call, as you say in England.”

Mary Debenham smiled a little in spite of herself. “Trunk call,” she corrected. “Yes, as you say, it is extremely annoying not to be able to get any word through, either by telephone or by telegraph.”

“And yet, Mademoiselle, this time your manner is quite different. You no longer betray the impatience. You are calm and philosophical.”

Mary Debenham flushed and bit her lip. She no longer felt inclined to smile.

“You do not answer, Mademoiselle?”

“I am sorry. I did not know that there was anything to answer.”

“Your change of attitude, Mademoiselle.”

“Don’t you think that you are making rather a fuss about nothing, M. Poirot?”

Poirot spread out his hands in an apologetic gesture.

“It is perhaps a fault with us detectives. We expect the behaviour to be always consistent. We do not allow for changes of mood.”

Mary Debenham made no reply.

“You know Colonel Arbuthnot well, Mademoiselle?”

He fancied that she was relieved by the change of subject.

“I met him for the first time on this journey.”

“Have you any reason to suspect that he may have known this man Ratchett?”

She shook her head decisively. “I am quite sure he didn’t.”

“Why are you sure?”

“By the way he spoke.”

“And yet, Mademoiselle, we found a pipe-cleaner on the floor of the dead man’s compartment. And Colonel Arbuthnot is the only man on the train who smokes a pipe.”

He watched her narrowly, but she displayed neither surprise nor emotion, merely said:

“Nonsense. It’s absurd. Colonel Arbuthnot is the last man in the world to be mixed up in a crime – especially a theatrical kind of crime like this.”

It was so much what Poirot himself thought that he found himself on the point of agreeing with her. He said instead:

“I must remind you that you do not know him very well, Mademoiselle.”

She shrugged her shoulders. “I know the type well enough.”

He said very gently:

“You still refuse to tell me the meaning of those words: ‘When it’s behind us’?”

She replied coldly, “I have nothing more to say.”

“It does not matter,” said Hercule Poirot. “I shall find out.”

He bowed and left the compartment, closing the door after him.

“Was that wise, my friend?” asked M. Bouc. “You have put her on her guard – and through her, you have put the Colonel on his guard also.”

“Mon ami, if you wish to catch a rabbit you put a ferret into the hole, and if the rabbit is there – he runs. That is all I have done.”

They entered the compartment of Hildegarde Schmidt.

The woman was standing in readiness, her face respectful but unemotional.

Poirot took a quick glance through the contents of the small case on the seat. Then he motioned to the attendant to get down the bigger suitcase from the rack.

“The keys?” he said.

“It is not locked, Monsieur.”

Poirot undid the hasps and lifted the lid.

“Aha!” he said, and turning to M. Bouc, “You remember what I said? Look here a little moment!”

On the top of the suitcase was a hastily rolled-up brown Wagon Lit uniform.

The stolidity of the German woman underwent a sudden change.

“Ach!” she cried. “That is not mine. I did not put it there. I have never looked in that case since we left Stamboul. Indeed, indeed, it is true!” She looked from one to another of the men pleadingly.

Poirot took her gently by the arm and soothed her.

“No, no, all is well. We believe you. Do not be agitated. I am sure you did not hide the uniform there as I am sure that you are a good cook. See. You are a good cook, are you not?”

Bewildered, the woman smiled in spite of herself, “Yes, indeed, all my ladies have said so. I–”

She stopped, her mouth open, looking frightened again.

“No, no,” said Poirot. “I assure you all is well. See, I will tell you how this happened. This man, the man you saw in Wagon Lit uniform, comes out of the dead man’s compartment. He collides with you. That is bad luck for him. He has hoped that no one will see him. What to do next? He must get rid of his uniform. It is now not a safeguard, but a danger.”

His glance went to M. Bouc and Dr. Constantine, who were listening attentively.

“There is the snow, you see. The snow which confuses all his plans. Where can he hide these clothes? All the compartments are full. No, he passes one whose door is open, showing it to be unoccupied. It must be the one belonging to the woman with whom he has just collided. He slips in, removes the uniform and jams it hurriedly into a suitcase on the rack. It may be some time before it is discovered.”