The investigators move on to the last of the first-class passengers, the American Mr. Hardman. Mr. Hardman confirms that he’s a traveling typewriter ribbon salesman, but on learning Hercule Poirot’s identity, he says he better “come clean.” He says his true occupation is a private investigator for a respected American detective agency.
Agatha Christie feints towards a more serious revelation when Hardman says he should come clean. When he states that he’s heard of Poirot and his work, it’s an admission that Poirot would find out his secret eventually. But the secret is, after all, an anticlimax. Hardman didn’t commit the crime or even have any special information about it; he’s simply a fellow detective.
Hardman reveals that he received the same offer of a job from Ratchett that Poirot did, but Hardman accepted. Ratchett even gave him a physical description of his potential murderer: a small, dark man with a feminine voice. Poirot shoots back, “You know who he really was, of course?” and goes on to describe Ratchett’s situation and the Armstrong case.
Hardman volunteers information that should be much more powerful than it is: a physical description of the man Ratchett thought was out to kill him. But the description is vague to the point of meaningless and can’t even definitively establish the gender of the suspect. Poirot tries to surprise Hardman by assuming “you knew who he really was” while leaving it ambiguous whether he’s referring to Ratchett or the suspect.
Continuing with his story, Hardman describes how he kept watch all night, describing Pierre Michel’s movements just as Pierre told Poirot. He notes that no one else could have boarded or left the train without him noticing.
Hardman corroborates the account of Pierre Michel and insists that no one could have boarded the train without him noticing. This places suspicion back on the current passengers in the Paris – Calais train car.
Hardman volunteers that he knew MacQueen by sight, having had dealings with his father, the district attorney. As Hardman goes, Poirot offers him both a cigarette and pipe, and Hardman takes the cigarette. Alone again, the investigators repeat the major new piece of information, that a small, dark man with a feminine voice was after Ratchett. Poirot observes that no one on the train fits that description.
Poirot again tries to get Hardman to act on instinct by offering a cigarette. In this situation, someone might act before remembering they had to disguise their habits. This is a suggestion that Poirot’s focus on “psychology” includes instinctive behavior. Nevertheless, Hardman takes the cigarette and Poirot is left with the vague description of the “small, dark man.” The fact that no one on the train fits that description points to an as-yet-undiscovered suspect, but the testimony of both Pierre Michel and Hardman suggests that no one boarded or left the train.