It is five o'clock on a cold windy morning in Syria. Detective Hercule Poirot is boarding the Taurus Express on his way to Stamboul (Istanbul) for a few days of vacation. As he boards the train Lieutenant Dubosc profusely thanks Poirot for his help, "You have saved us mon cher...you have saved the honor of the French Army." To which Poirot replies, "But indeed, do I not remember that you once saved my life?" After exchanging more pleasantries with the General, Poirot boards the train. On the train he is accompanied by Mary Debenham and Colonel Arbuthnot whom Hercule first encounters at breakfast that same morning. While sipping coffee, Poirot observes every detail of Arbuthnot and Debenham. Arbuthnot approaches Debenham, already eating breakfast, and asks if he might join her. The two, "true to their English nationality," were "not chatty." At two-thirty the train comes to a halt because of a fire under the dining car. Mary Debenham is extremely anxious and tells Poirot that she must not miss her connection to the Simpleton Orient Express. Poirot observes the Mary and the Colonel become increasingly friendly over the course of their voyage to Istanbul and overhears conversations between them that peak his detective's curiosity. While looking out at the scenery, Mary remarks to Arbuthnot that she wishes she could enjoy the countryside. And, at the Konya stop, when Poirot and the couple get out to stretch their legs, Poirot hears Arbuthnot and Mary speaking together; Mary says to Debenham "When it's all over. When it's behind us—then—."
Poirot arrives in Stamboul and checks in at the Tokatlian Hotel. There are three letters and a telegram waiting for him. The telegram informs him that there is a development in the Kasner case and he must return to London. Poirot arranges a room on the Simpleton Orient Express, which will leave at nine that evening. In the hotel restaurant Poirot meets up with an old friend M. Bouc, director of the Compagnie Internationale des Wagons Lits, who will accompany him on the train. While eating in the restaurant, Poirot takes interest in two men, Ratchett and Hector McQueen, at a nearby table. Poirot is immediately distrustful of Ratchett. After Poirot finishes his meal he meets M. Bouc in the lounge. The concierge enters and tells Poirot there are no first class apartments available. Surprised at the full train, he remarks to Poirot, "All the world elects to travel to-night!" M. Bouc arranges for Poirot to take the carriage of Mr. Harris, a man who has not yet shown up for the train. Poirot shares the carriage with Hector McQueen-the same young man he saw with Ratchett in the restaurant.
The next day M. Bouc lunches with Poirot. While the two men sit and eat, Poirot looks around at the other thirteen passengers: a "big, swarthy Italian;" a neat Englishman; a big American, one of the "ugliest old ladies he had ever see—Princess Dragomiroff; Mary Debenham sitting with two other women; Colonel Arbuthnot by himself; a middle-aged Scandinavian woman; an English- looking couple and, lastly, Hector McQueen and Ratchett. The dining car empties and Ratchett comes and sits opposite Poirot. Ratchett tells Poirot that he has enemies and that his life is threatened. He offers Poirot "big money" to protect him. Poirot tells Ratchett that he only takes cases that "interest him." Ratchett asks Poirot why he won't take the case. Poirot replies, "I do not like your face."
The character of Hercule Poirot is set up and detailed in the first three chapters. The personality traits and ticks he displays in these chapters not only color him and make him an incredibly interesting character, but help set up his motivations and detective technique for the rest of the novel.
Poirot is introduced as the "Belgian stranger" that has some connection with a suicide, a General and the French Army. All very suspicious and left purposefully ambiguous. From the point of view of Lieutenant Dubosc, Poirot is described as a mysterious, small man "muffled up to the ears of whom nothing was visible but a pink tipped nose and an upward curled moustache." It is only in the first few chapters that Poirot is scrutinized from another character's perspective, from then on the reader mainly concentrates on the murder suspects. Poirot's moustache is another particularly wonderful detail, especially in Chapter 2 as he makes pains to keep it out of his soup.
The reader immediately knows that Poirot is obviously a trained and successful detective; he is short, worrisome and self-conscious. Poirot probably does not have a family, as they are never mentioned and are not on vacation with him, but is a single bachelor that has little interest in women. Poirot is not an infallible character, but has insecurities and issues like the rest of the passengers.