Here you will find a Murder on the Orient Express summary (Agatha Christie's book).
We begin with a summary of the entire book, and then you can read each individual chapter's summary by visiting the links on the "Chapters" section.
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The renowned retired detective, Hercule Poirot, embarks on a train journey to Istanbul, sharing his ride with Mary Debenham and Colonel Arbuthnot, who seem intimately acquainted despite pretending to be strangers. Upon reaching Istanbul, Poirot is summoned back to London, and while waiting for his return journey, he encounters his old acquaintance, M. Bouc, who arranges for his accommodation on the Orient Express. In the interim, Poirot crosses paths with Ratchett and Hector McQueen, who arouse his suspicion, particularly Ratchett, who approaches him for protection against death threats, but is rebuffed by Poirot. Despite the train being unusually crowded, Poirot manages to secure a first-class cabin where he experiences a series of peculiar incidents, including a cry from Ratchett's compartment indicating possible danger. The following morning, Poirot is informed by M. Bouc that Ratchett has been brutally murdered, prompting Poirot to launch an investigation. A detailed examination of Ratchett's compartment reveals multiple clues such as twelve stab wounds on Ratchett's body, an open window, and a handful of miscellaneous items that include a handkerchief with an initial "H", a peculiar match, and a burnt piece of paper with the name "Armstrong" on it. This leads to Poirot deducing that Ratchett was actually Cassetti, the infamous kidnapper and murderer of the toddler, Daisy Armstrong, whose crime had shocked the nation. Poirot proceeds with interviewing the passengers, starting with Hector McQueen, who was startled that Poirot had discovered the Armstrong note, believed to have been destroyed. Several interviews subsequently provide Poirot with potential alibis, but also raise doubts about the identity of an unseen woman in a red kimono and the presence of an unfamiliar man in a Wagon Lit uniform. A thorough examination of the passengers' belongings brings forth more suspicious findings, leading Poirot to unveil the true identities of several passengers who were closely connected with the Armstrong case. Finally, Poirot presents two possible explanations for the murder and reveals the collective guilt of twelve passengers, all of whom were connected to Daisy Armstrong. To protect the involved parties, Poirot proposes that the authorities be informed of the less plausible theory, which is ultimately agreed upon by M. Bouc and Dr. Constantine.
On a chilly dawn in Syria, renowned detective Hercule Poirot hops onto the Taurus Express, bound for a brief holiday in Stamboul (Istanbul). Lieutenant Dubosc, brimming with gratitude, hails him, "You have saved us mon cher...you have saved the honor of the French Army." Poirot responds, "But indeed, do I not remember that you once saved my life?" Following cordial exchanges with the Lieutenant, he steps onto the train, where he meets Mary Debenham and Colonel Arbuthnot at breakfast. As he enjoys his coffee, he scrutinizes both of them. Arbuthnot, seeking Debenham's company at breakfast, finds her already seated. Their conversation is sparse, in line with their "English nationality." An unexpected halt at two-thirty, due to a fire in the dining car, makes Debenham panicky. She fears missing her transfer to the Simpleton Orient Express. As the journey towards Istanbul proceeds, Poirot notices a growing camaraderie between Mary and the Colonel. Their conversation fuels his detective instincts. Mary, while admiring the landscape, expresses a longing to Arbuthnot to enjoy the countryside. During a halt at Konya, Poirot eavesdrops on their exchange. Mary tells Arbuthnot, "When it's all over. When it's behind us—then—."
Upon reaching Stamboul, Poirot lodges at the Tokatlian Hotel. He discovers three letters and a telegram awaiting his attention. The telegram urges him to return to London due to a new development in the Kasner investigation. Consequently, Poirot books a room on the nine o'clock Simpleton Orient Express. He encounters an old colleague, M. Bouc from Compagnie Internationale des Wagons Lits, at the hotel restaurant who plans to join him on the train. Poirot grows curious about two men, Ratchett and Hector McQueen, dining nearby, with Ratchett earning Poirot's suspicion. After his meal, Poirot and M. Bouc meet in the lounge where they learn from the concierge that no first class compartments are left. Poirot is taken aback by the crowded train and the concierge observes, "All the world elects to travel to-night!" M. Bouc manages to secure Mr. Harris's carriage for Poirot when it appears Mr. Harris is a no-show. Poirot finds himself sharing the carriage with Hector McQueen, the man he observed with Ratchett earlier.
As M. Bouc and Poirot share a meal, Poirot observes the various passengers: a robust Italian, a tidy Englishman, a large American, the unattractive Princess Dragomiroff, Mary Debenham and two other ladies, solitary Colonel Arbuthnot, a middle-aged Scandinavian lady, a British couple and finally, Hector McQueen and Ratchett. After the dining area has cleared, Ratchett joins Poirot, expressing fear for his life due to some enemies and proposes to pay Poirot a large sum for his protection. Poirot declines, stating he only undertakes cases that "interest him." When Ratchett inquires why Poirot won't consider his case, Poirot's response is simple - "I do not like your face."
The Orient Express rolls into Belgrade at 8:45. Poirot steps out for fresh air, only to retreat back due to the harsh chill. He's informed by the conductor that his belongings have been shifted to cabin one in M. Bouc's car. This move, facilitated by M. Bouc's shift to the Athens coach, places Poirot in first class, next to Mr. Ratchett and two cabins from Mrs. Hubbard. While navigating his way back, Mrs. Hubbard accosts Poirot, confessing she is "dead scared" of Ratchett. She divulges hearing Ratchett attempting to unlock the adjoining door between their cabins the previous night. As this conversation unfolds, Poirot overhears McQueen inviting Arbuthnot to his carriage for a discussion on India. After bidding Mrs. Hubbard goodnight, Poirot retreats to his cabin, engrosses himself in reading for an hour or two and subsequently falls asleep. He wakes up later to a resounding groan, followed by a bell tolling. The halted train suggests they are at a station. A knock echoes from Mr. Ratchett's door. A responding voice says, "Ce n'est rien. Je ne suis trompe." The conductor, content with the response, moves further down the hall to another door with a lit light. Poirot checks his watch; it's 23 minutes to one in the morning.
Struggling to sleep with the quietness of the halted train, Poirot hears some noises in the corridor, including the persistent ring of a conductor's bell and Mrs. Hubbard's claim of a man in her compartment. He requests some water from the conductor who reveals that the train is stuck in a snow bank, potentially for days. Just as Poirot is about to sleep, a loud sound from the neighboring compartment, occupied by Ratchett, catches his attention. Looking out, he sees only a woman in a red kimono and the conductor busy with some paperwork. The next morning, with the train still unmoving, Poirot joins the other guests in the dining car. The mood is tense as passengers worry about missed schedules. Post breakfast, M. Bouc summons Poirot and shares the shocking news that Ratchett has been murdered. The autopsy, conducted by Dr. Constantine, reveals multiple stab wounds and rules out suicide. The window of the victim's compartment is found open, which M. Bouc suspects as a deliberate attempt to mislead the investigation. The absence of any footprints in the snow outside the window and the locked door from inside confirm the murderer to be still aboard in the Stamboul-Calais coach. M. Bouc implores Poirot to take up the case, which he obliges.
Passports and tickets from all the passengers are collected. Poirot begins his inquiries with Hector McQueen, a younger man he had spotted with Ratchett. Poirot informs McQueen of Ratchett's demise. McQueen shows minimal surprise and responds with, "So they got him after all." He shares with Poirot that he was employed as Ratchett's assistant for over a year. McQueen's language skills were useful as Ratchett was monolingual. He adds that Ratchett, or Samuel Edward Ratchett as was his full name, was an American who seemed to be avoiding something. Ratchett had started receiving ominous letters a few weeks prior. McQueen presents Poirot with one such letter. Poirot assesses it was penned by multiple individuals. McQueen’s final encounter with Ratchett was at 10 PM, when he jotted down some notes for him. After the interaction, McQueen is excused.
Guided by Dr. Constantine, Poirot examines the untouched crime scene in Ratchett's compartment, where the deceased is found. They discover that some knife wounds were inflicted post-mortem, with a mix of right-handed and left-handed strikes. The severity of the blows also differs, with some deep, others superficial. Poirot takes note of two varieties of matchsticks in the ashtray—round and flat, leading him to believe the latter might belong to the killer. They also uncover an initialled handkerchief, a pipe cleaner and Ratchett's watch showing the time as 1:15. A partially burned paper also catches Poirot's attention. Using a spirit stove, tongs, and a hat box's netting, he manages to decipher the words, "—member little Daisy Armstrong." This strikes a chord in Poirot, who realizes that Ratchett's real identity is Cassetti, an American.
Over a meal, Poirot reveals to Dr. Constantine and M. Bouc that M. Ratchett is in fact Cassetti, responsible for the abduction and murder of Daisy Armstrong. Daisy was the only child of Colonel Armstrong, a wealthy Wall Street tycoon, and well-known actress Linda Arden. Despite paying a hefty $200,000 ransom, Daisy was found dead. This led to a series of tragic events; Mrs. Armstrong prematurely gave birth to a stillborn, Colonel Armstrong committed suicide out of grief, and their nursemaid, under suspicion for involvement in the crime, also took her life. Despite his arrest, Cassetti evaded punishment due to his wealth and influence. Poirot theorizes that the murderer destroyed the burnt paper to sever ties with the Armstrong name.
In the train's dining car, Poirot commences an inquiry. He summons Pierre Michel, the Wagon Lit conductor, known for his honesty and over fifteen years of service. Pierre recounts his prior evening's movements to Poirot. He mentions Ratchett's request for bed-making during dinner so he could sleep early. He saw Hector McQueen entering Ratchett's compartment later. Around 12:40 A.M., Ratchett rang him, then claimed it was an error when Pierre arrived. He later visited a colleague in the Athens coach but was summoned by Mrs. Hubbard's and then Poirot's bell past 1 A.M. Half an hour later, Pierre made McQueen's bed, who had been engaged in conversation with Colonel Arbuthnot. He noticed a lady in a red dragon kimono but no other activity in the corridor. Pierre further assures Poirot of a thorough search of the train, negating the possibility of a hidden murderer. The last halt was at Vincovci at 11:58, where he alighted with fellow conductors.
Poirot brings Hector McQueen in for another talk, revealing Ratchett's true identity and past crime. Caught off guard, McQueen assures Poirot that he wouldn't have been Ratchett's employee had he known the truth, as his father was the DA on the Armstrong case and he felt a strong connection to the family. After dinner, McQueen went back to his cabin and read for a while before striking up a conversation with Colonel Arbuthnot in Belgrade. They had a lengthy political discussion that lasted until 2AM in McQueen's cabin, after which McQueen fell asleep. McQueen and Arbuthnot alighted at Vincovci for some fresh air. The only individual McQueen recalls seeing was a lady in a bright silk dressing gown crossing his door, but he didn't see her come back.
Poirot interviews Ratchett's valet, Edward Henry Masterman. Masterman recounts his last interaction with Ratchett around 9PM, when he assisted with Ratchett's evening routine. Ratchett was noticeably anxious and curtly instructed Masterman not to disturb him until summoned the following day. Masterman wasn't surprised when Ratchett didn't summon him the next morning as Ratchett was known to sleep late. After leaving Ratchett, Masterman relayed a message from Ratchett to McQueen before retiring to his shared compartment with an Italian man. Masterman spent the night reading until 10:30PM, when the conductor prepared the beds. He struggled to sleep until 4AM due to toothache. He was aware that Ratchett had enemies, having overheard discussions between Ratchett and McQueen about threatening letters. However, he was unaware of Ratchett's true identity. He did, however, know about the Armstrong case. The interview also reveals that Masterman is a smoker.
Mrs. Hubbard urgently relays to Poirot that she believes the killer was in her compartment. She had dozed off the previous night, only to be jolted awake with the feeling of a man's presence in her room. Fearfully, she rang for the conductor while keeping her eyes shut. By the time the conductor arrived, there was nobody in her compartment. For safety, she had requested the conductor to bolt the door connecting her room to Ratchett's, and she also barricaded it with a suitcase. Unsure of the exact timing of these events, Mrs. Hubbard also hands over a button she discovered on her cabin floor, identical to the ones the Wagon Lit conductor wears. Poirot brings up the Armstrong case, and while Mrs. Hubbard insists she wasn't close with the Armstrongs, she is emotionally invested in the case and is outraged that the killer escaped justice. Poirot reveals Ratchett's true identity as Cassetti, the murderer in that case, shocking Mrs. Hubbard. Poirot also confirms that Mrs. Hubbard neither owns a red nightgown nor the handkerchief found in Ratchett's room.
Greta Ohlsson undergoes questioning next. She is believed to be the last one to interact with Cassetti (Ratchett). She accidentally entered his compartment, mistaking it for Mrs. Hubbard's. Inside, Ratchett was reading. On leaving Mrs. Hubbard's room, Mrs. Hubbard requested Greta to secure the connecting door. Subsequently, around 10:55, Greta retreated to her own sleeping space. She shares her room with Mary Debenham, who Greta asserts didn't leave once during the night. Greta doesn't own a red dressing gown. She wasn't aware of the Armstrong case and was deeply disturbed upon learning about the abduction.
Upon finding the conductor's uniform button in her room after the homicide, Mrs. Hubbard immediately summons Pierre Michel. M. Bouc inquires if Michel can shed light on the situation, but his buttons are accounted for and he has no further information. He becomes irate at the implication of his involvement, bringing in his coworker from another car to confirm his alibi, which he does without hesitation. Once cleared, Michel leaves and Princess Dragomiroff is brought in for interrogation. The Princess informs Poirot that she went straight to bed after dinner the previous night, reading until 11 p.m. Close to 12:45 a.m., she called her maid, Hildegarde Schmidt, for a massage and bedtime story until falling asleep. During this period, she heard no peculiar noises. She discloses her close relationship with the Armstrong family, with their daughter, Sonia, being her godchild. The Princess also mentions a younger Armstrong daughter whom she has lost contact with. The Princess has a black satin dressing robe. She inquires about Poirot's identity, and upon hearing his name, she says, "Yes. I remember now. This is Destiny."
The inquiry continues with Count and Countess Andrenyi, though only the Count shows up. He dismisses any possibility of being helpful, claiming neither he nor his wife were disturbed that night. His indifference remains even when Poirot discloses Ratchett's true identity. The Count professes ignorance of the Armstrong clan. He insists they spent the night in their compartment (No. 13), playing piquet until 11, when they retired for the night. Despite the Count's objections, Poirot demands to see the Countess. Her passport, bearing a grease stain and the name Elena Maria Goldenberg, reveals she is only 20. Upon Poirot's insistence, the Count brings the Countess. She supports her husband's account and denies ever joining the Count to America. She also mentions that the Count smokes both cigarettes and cigars, and she owns a corn-colored chiffon bathrobe.
Poirot engages Colonel Arbuthnot in a discussion. Arbuthnot discloses his trip from India to Syria was "for his own reasons" and he first encountered Miss Debenham on the same train ride they had with Poirot, from Kirkuk to Nisibin. Poirot inquires about Arbuthnot's impressions of Miss Debenham, to which he replies, "She is a lady" and denies the possibility of her involvement in the murder. Arbuthnot recounts spending the prior night discussing Indian politics with Hector McQueen. He states that he and McQueen briefly stepped out at Vincovci before quickly retreating back due to freezing temperatures. In McQueen's compartment, they shared a smoke—Arbuthnot using a pipe. He only remembers a woman with a distinct fruity perfume passing by. Around 2:45, he left for his compartment, noticing the conductor at the corridor's end. He further recollects noticing a partially open door of No. sixteen, with a man surreptitiously looking out, who abruptly closed the door when Arbuthnot came nearer.
The American from berth No.16, Mr. Hardman, is the final first class passenger brought in for interrogation. Though his passport identifies him as a sales representative for typewriter ribbons, he discloses his real profession to Poirot—Cyrus B. Hardman, a private investigator from McNeil's Detective Agency, New York City. Initially in Europe to track down a few criminals, he was afterwards employed by Ratchett due to fears of being murdered, evidenced by several ominous letters. Ratchett had described his potential attacker as a petite, dark-skinned man with a feminine voice. Although Hardman was supposed to occupy the cabin next to Ratchett, he was allocated No.16. His strategy was to leave his door ajar to monitor the corridor, but he didn’t see anyone suspicious the night Ratchett was slain. Hardman is taken aback when he learns that Ratchett is actually Cassetti, the infamous Armstrong kidnapper, as he was in the West during the case and likely wouldn't recognize Cassetti.
The questioning of Antonio Foscanelli, an Italian who has claimed America as his home for a decade and is employed by Ford, ensues. Antonio, who spent the evening with Hardman, an American, before retiring to his berth, confesses to his unfamiliarity with the Armstrongs or the associated scandal. His rooming partner, John Bull, disturbs his slumber with his groaning. Antonio's pastime involves smoking cigarettes.
Mary Debenham, a poised 26-year-old English woman, is questioned by Poirot. She recounts going to bed on the night of the murder, waking up at five when she noticed the stationary train. Looking out her cabin, she sees a tall, thin woman in a scarlet kimono and a shingle cap. She feels relatively unaffected by the murder, having only briefly seen Ratchett the day before. Mary provides information about her cabin mate, Greta Ohlsson. She describes Greta as a pleasant woman who owns a brown wool dressing gown. Poirot acknowledges Mary's own dressing gown as the pale mauve one he saw on the train to Stamboul. Before leaving, Mary mentions Greta's concern about being under suspicion as she was the last to see Ratchett alive. Mary noticed Greta leaving around 10:30 to give Mrs. Hubbard aspirin and returning shortly after. Poirot inquires from the doctor about the possibility of Ratchett being murdered that early, to which the doctor denies. Poirot assures Mary that Greta is not a suspect.
Poirot, the doctor, and M. Bouc express their suspicion towards Mary Debenham, due to a conversation overheard on the train to Stamboul. They believe she’s capable of methodically planning a murder. Next, Poirot gently interrogates Hildegarde Schmidt, Princess Dragomiroff's maid. He asks about her activities the night of the crime. Schmidt recalls going to the Princess's room after being awoken by an attendant, providing a massage, and reading to the Princess until she slept. Afterward, she went back to sleep. On her way, she encountered the conductor near the Princess's compartment, who almost ran into her and quickly apologized. Mrs. Hubbard's bell was ringing, but he didn't respond. Despite Poirot presenting the car attendants, none of them were the man Schmidt bumped into, who was described as small and dark. Schmidt becomes emotional when discussing the Armstrong case. She denies owning the handkerchief found in Ratchett's room and doesn't seem to know who it belongs to—but Poirot senses a hesitation in her voice.
The interrogation concludes with Hildegarde Schmidt, the train staff, and the doctor. Alone in the dining car, M. Bouc and Poirot consider all passenger testimonies. Poirot confirms that Ratchett, or Cassetti, was stabbed twelve times last night. He presents three possible timings of the murder: at 1:15, as the broken watch, Mrs. Hubbard and Schmidt's testimonies, and the doctor's findings suggest; later than that, with fabricated evidence; or even earlier, with manipulated evidence too. The existence of the petite, effeminate-voiced man, identified as a potential killer by Hardman and as a sleeping-car attendant by Schmidt, isn't conclusively proven. Poirot trusts Hardman's self-description, but doubts the veracity of his account of last night's events. Schmidt's statement, the discovery of the attendant's button in Mrs. Hubbard's room, and the attendant mentioned by Arbuthnot and McQueen lend support to the effeminate man theory. M. Bouc informs Poirot that a thorough train search found no such man. Poirot suggests two alternatives: the man is hiding somewhere or there are multiple murderers. They decide to inspect passenger belongings for the red kimono and sleeping-car jacket. Right then, Mrs. Hubbard intrudes, exclaiming, "It's just too horrible. In my sponge-bag. My sponge-bag! A great knife—all over blood!" She then collapses onto M. Bouc's shoulder.
M. Bouc and Poirot went to Mrs. Hubbard's compartment as all passengers were already there. An unexpected sight awaited them - a large, rubber sponge-bag was suspended from the handle of the door that linked Ratchett's and Mrs. Hubbard's compartments. Below lay a knife with an ornate hilt and a straight blade, which appeared rusty. The doctor confirmed the blade was capable of inflicting Ratchett's wounds. Poirot attempted to manually unlock the door, to no avail. Noting the position of the bolt above the handle, Poirot questioned Mrs. Hubbard, who had recovered from her faint, again about the conversation with Greta Ohlsson regarding the locking of the door. Mrs. Hubbard maintained that Ohlsson had checked the door and it was locked. Poirot proposed that Ohlsson might have mistakenly thought the bolted door was locked when she tried it. This puzzled Poirot as the bolt was not under the sponge-bag. Mrs. Hubbard was then moved to another coach, and despite a thorough search of her belongings, no incriminating evidence was found.
While rummaging through the belongings of the train's occupants, Poirot and M. Bouc discover several intriguing articles. They unearth pipe-cleaners identical to those in Ratchett's compartment from Colonel Arbuthnot's items, a damp tag on Countess Andrenyi's luggage, and the infamous red kimono neatly tucked above Poirot's suitcase, likely placed there by the audacious murderer. During this search, Poirot converses with a resentful Princess who confesses her fondness for Sonia Armstrong, the mother of the abducted toddler. He also interacts with Mary Debenham who remains tight-lipped about her discussion with Colonel Arbuthnot on their Stamboul journey. When asked about her statement to Arbuthnot - "Not now. Not now. When it's all over. When it's behind us," she asserts that she can't disclose the meaning behind "being over." However, she staunchly asserts that she hadn't met Ratchett prior to their Orient Express journey and refutes any prior acquaintance with Arbuthnot.
In the dining carriage, Poirot, M. Bouc, and the doctor deliberate over the clues they've uncovered. Poirot is particularly fascinated by the investigation as he's unable to use conventional detective methods and instead must rely solely on his wits. His companions, M. Bouc and the doctor, however, remain sceptical. They first discuss Hector McQueen who persistently told Poirot that Ratchett couldn't speak French. Therefore, the voice from Ratchett's compartment at 12:47 must have been someone else, someone who was fluent in French. Poirot then highlights that the only feasible opportunity for someone to break into Ratchett's compartment was when the train was stationary at Vincovci station or when the conductors disembarked. Otherwise, the only time the conductor was absent from his post was between 1 a.m. and 1:15 a.m. Poirot compiles a list of passengers, theorizing their potential motives for the murder, and their alibis.
Poirot is striving to answer several questions: identifying the owner of the handkerchief found in Ratchett's compartment; the individual who dropped the pipe cleaner; the wearer of the scarlet Kimono and the Wagon Lit uniform; figuring out why Ratchett's timepiece stopped at 1:15; determining the exact time of the crime; and ascertaining the number of culprits involved. He concludes that the handkerchief might've been unintentionally dropped, but deems the pipe cleaner a misleading clue. Despite his efforts, M. Bouc cannot unravel the mystery, leaving him perplexed, particularly regarding the broken watch. Poirot reveals that he made all the passengers sign their names, noting that all but Princess Dragomiroff, who abstained, used their right hand, potentially explaining the right-handed and left-handed inflicted wounds on Ratchett. The doctor asserts that the varying manners of the inflicted blows suggest multiple culprits.
After a period of silence, M. Bouc and Dr. Constantine express their confusion, but Poirot hints at having some understanding. He highlights several key clues: "a remark made by M. Bouc...we were surrounded by people of all classes, of all nationalities...somewhat rare at this time of year...the position of Mrs. Hubbard's sponge-bag, the name of Mrs. Armstrong's mother, the detective methods of M. Hardman, the suggestion of M. McQueen that Ratchett himself destroyed the charred note we found, Princess Dragomiroff's Christian name, and a grease spot on a Hungarian passport." Poirot suspects Countess Andrenyi is actually Helena Goldenberg, kin to Linda Arden and Mrs. Armstrong. He theorizes that the burnt note, contrary to McQueen's claim, was intentionally destroyed to remove any link to the Armstrong family, implying the killer has strong ties to them. The Countess deliberately smeared grease on her passport to conceal her name and deflect suspicion. It's also suggested that Princess Dragomiroff deceitfully claimed ignorance of Helena's location.
Poirot confronts the Count and Countess Andrenyi with the knowledge that the Countess is actually Helena Goldenberg, Mrs. Armstrong's sister. Despite her husband's initial denial, Helena admits the truth. She kept her identity hidden as she had the strongest reason to kill Ratchett - he had caused her family significant suffering. However, she insists she never harmed Ratchett and stayed in her compartment. The handkerchief with an "H" found in Ratchett's room isn't hers. Poirot questions her about the Armstrong case, namely the death of Daisy's French nursery maid, Suzanne, who killed herself when she thought she was a suspect. The Countess also provides information about Daisy's nurse, a hospital-trained woman named Stengleberg, and her own governess, Miss Freebody, a "big red-haired woman" of Scottish descent. Apart from Princess Dragomiroff, Helena doesn't recognize anyone else on the train.
Following the Countess Andrenyi's testimony, M. Bouc is convinced she is guilty. Poirot, however, is not as certain. He believes the Count's assertion that his wife may not be involved. Princess Dragomiroff approaches Poirot, stating, "I believe, Monsieur...that you have a handkerchief of mine." Poirot hands her the handkerchief, his suspicions confirmed. The Princess discloses that the "H" is actually the Russian letter "N" and is unaware how it ended up in Ratchett's room. Even though she hid Countess Andrenyi's identity, she maintains she's telling the truth. The doctor vouches for her, stating she physically couldn't have committed the murder, "never, never, could anyone with so frail a physique inflict them." Poirot is reminded of something the Princess said earlier about her physical strength being greater than her willpower. M. Bouc is shocked by the layers of deception among the passengers, to which Poirot replies, "there are still more to discover."
Colonel Arbuthnot is called upon for another meeting. Immediately, Poirot questions him regarding the pipe cleaners found in Ratchett's room. Arbuthnot denies leaving them there, stating he never even conversed with Ratchett. Poirot then inquires if it's possible he killed Ratchett without ever speaking to him. Arbuthnot vehemently denies this. Poirot brings up Mary's statement at the Koya station again, "Not now. When it's all over. When it's behind us," but Arbuthnot remains tight-lipped about it.
Mary Debenham is questioned by Poirot in the dining car, where he confronts her about her deceit concerning her time spent in the Armstrong household during the murder. She confesses to her deception, explaining that she feared her association with the Armstrongs would deter future employers. Despite time and her altered appearance, Mary did not recognize Countess Andrenyi, whom she hadn't seen in three years. Overwhelmed, Mary becomes emotional and is defended by Colonel Arbuthnot. The pair then exit the dining car. M. Bouc continues to be impressed by Poirot's investigative prowess, unsure of how he identified Mary's involvement with the Armstrongs. In response, Poirot reveals that he was clued in by the Countess' determined effort to shield Mary. He points out that the Countess' portrayal of her governess as a large, red-haired woman starkly contrasts Mary's appearance. Additionally, the Countess inadvertently indicated her connection to Mary by using the name Freebody, which corresponds with the name of a London store, Debenham and Freebody, revealing it as the first name that came to her mind.
M. Bouc expresses his suspicion that each passenger on the train might be linked to the Armstrongs, a sentiment Poirot finds insightful. Antonio Foscanelli, the Italian, gets summoned back to the dining car. Once a chauffeur for the Armstrongs, Foscanelli vehemently denies killing Ratchett. He recalls Daisy, who he describes as "the delight of the house," and her playful imitation of driving. Next, Greta Ohlsson gets called in. Overwhelmed with emotion, she confesses to being Daisy Armstrong's former nurse, and regrets her prior silence. Following her, Masterman steps in, instantly revealing to Poirot his past as Colonel Armstrong's wartime orderly and later valet. He vouches for Antonio, insisting the latter "wouldn't hurt a fly." Hardman comes in after Masterman. Poirot questions if he is somehow tied to the Armstrongs, but Hardman denies any association. He believes he might be the only person on the train without Armstrong connections. He inquires Poirot about the identities of the American woman and her maid. Poirot playfully suggests they could be a cook and a housekeeper. Hardman then asks if Poirot has figured out who killed Ratchett. Poirot's response is, "I have known for some time," and instructs Hardman to gather all passengers in the dining car.
Passengers gather in the dining car. Greta Van Ohlsson continues crying. Poirot shares that the crime has two potential solutions, leaving the final verdict to Dr. Constantine and M. Bouc. The first solution, says Poirot, involves the man Mr. Hardman was warned about. This man got on the train at Vincovci using the door left open by Arbuthnot and McQueen, and dressed as a Wagon Lit employee, he killed Ratchett. Ratchett's watch stopped at 1:15 because he forgot to adjust it in Tzaribrod, suggesting the murder took place at 12:15 a.m. An unidentified third person in the compartment was responsible for the 12:47 voice. For the second theory, Poirot recalls a comment from M. Bouc about the diverse passengers only possible in America. Poirot’s second conversation with McQueen also aroused suspicion, as McQueen seemed to know about the Armstrong note. Furthermore, Masterman's claim of Ratchett's habitual sleeping draught use didn't add up as Ratchett feared someone was trying to kill him. Hardman's testimony confirmed the murderer was onboard the coach. The intimate interaction between Miss Debenham and Colonel Arbuthnot exposed they were not strangers. Mrs. Hubbard's claim of having Greta Ohlsson check the door bolt seemed false, as she could have seen it herself. Poirot determines that the 12:47 scream wasn't from Ratchett, due to lack of struggle signs and Ratchett’s inability to speak French. Poirot assumes this scene was staged, suggesting the murder took place near two in the morning. Considering the difficulty of pinning the crime on one person and the numerous passengers with Armstrong ties, Poirot concludes they all conspired to murder Ratchett. He believes they formed a makeshift jury, executing Ratchett for escaping justice in the US. Poirot identifies the Wagon Lit conductor as a conspirator, leaving thirteen related to the case. He asserts that Princess Andrenyi is innocent, and her husband acted on her behalf. He reveals Mrs. Hubbard as Linda Arden, Sonia Armstrong's mother. Mrs. Hubbard confirms her identity and reveals the plot, justifying their actions as carrying out Cassetti’s escaped death sentence. She requests Poirot to only implicate her, sparing the others. Poirot consults with Dr. Constantine and M. Bouc. M. Bouc proposes presenting the first solution to the police, while the Doctor concedes he may have made some outlandish suggestions.