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. Bow 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.”
“And then?” said M. Bouc.
“That we must discuss,” Poirot said with a warning glance.
He held up the tunic. A button, the third down, was missing. Poirot slipped his hand into the pocket and took out a conductor’s pass-key, used to unlock the doors of the compartments.
“Here is the explanation of how one man was able to pass through locked doors,” said M. Bouc. “Your questions to Mrs. Hubbard were unnecessary. Locked or not locked, the man could easily get through the communicating door. After all, if a Wagon Lit uniform, why not a Wagon Lit key?”
“Why not indeed?” returned Poirot.
“We might have known it, really. You remember that Michel said that the door into the corridor of Mrs. Hubbard’s compartment was locked when he came in answer to her bell.”