Poirot begins calling the passengers for interviews to give their accounts of the previous night and early morning.
This chapter begins to lay out the form the investigation will take: a series of interviews in which Poirot will attempt to compare stories, but also to get to the “psychological” truth of the case. Tellingly, this part of the novel is titled The Evidence, seeming to suggest that there’s an entire realm of it beyond physical evidence.
First up is Pierre Michel, the conductor, who seems a bit shaken and flighty. Poirot asks him to describe the events of last night, including ones that Poirot himself witnessed. Pierre relates that only Mr. MacQueen was in Ratchett’s cabin that night. After hearing the groan that woke Poirot, Pierre rapped on the door of Ratchett’s room to check on him, and Ratchett called out in French to reassure him.
Matching the events of the night to what Poirot already knows, the response from Ratchett in “French” leaps out as suspicious. MacQueen has already noted that he was brought on by Ratchett to assist with languages, as Ratchett only knows English.
Pierre Michel confirms that Mr. MacQueen talked in his cabin with Colonel Arbuthnot late into the night. After making up MacQueen’s cabin, Pierre Michel talked with another conductor in the adjacent train car until he was summoned by Mrs. Hubbard. He attended to her and then to Poirot, and then sat in his place awake for the rest of the night. He also remembers a woman in a scarlet kimono walking down the hallway.
Pierre confirms MacQueen’s story: that he was talking late with Colonel Arbuthnot. He also confirms the existence of a woman in a scarlet kimono. The nature of the garment itself, as a boldly colored and exotic dressing gown, calls special attention to itself.
Pierre Michel almost omits a detail about Poirot poking his head out close to 2 a.m., with Poirot adding “Good my friend…I wondered whether you would remember that.” Pierre claims that there is no way someone either boarded the train at the previous stop or has hidden undiscovered somewhere on the train.
Pierre’s testimony lends credence to the theory that the Paris-bound sleeping car is a “locked room” and that Ratchett’s murderer is currently on the train. Poirot also reveals some of his detective style here. He gently tests Pierre Michel on what he would have seen if his account is truthful—for example, Poirot looking out into the hallway.
Pierre Michel seeks validation from both Poirot and M. Bouc that he hasn’t been negligent in any way. They reassure and then dismiss him.
Throughout his testimony, Pierre has been anxious that he’d made a mistake in handling the events of the night and early morning. Poirot had leaned on that slightly in his questioning, praising his recall to put him more at ease.