Mrs. Hubbard rushes into her interview and announces that she has very important information about the murder. She tells Poirot that the murderer was actually in her compartment. The previous evening, she had fallen asleep, but was suddenly awakened in the night and knew a man was in her compartment. Mrs. Hubbard had lain in her bed, with her eyes tightly closed and pressed the bell for the conductor. When the conductor finally came there was not anyone in her compartment. Mrs. Hubbard told Poirot that she had asked the conductor to make sure the communicating door between her compartment and Ratchett's was bolted and for extra safety she placed a suitcase in front of the door as well. Mrs. Hubbard was not sure what time all of this happened. The lady also gives Poirot some evidence—a button she found on the floor of her compartment. The button is the same as the Wagon Lit conductor's. Poirot asks Mrs. Hubbard if she has heard of the Armstrong case. Mrs. Hubbard tells Poirot she was not intimately acquainted with the family, but feels strongly about the case and is particularly upset that the murderer got off. She is terribly excited when Poirot tells her that Ratchett is Cassetti, the murderer. Poirot also finds out that Mrs. Hubbard does not have a scarlet nightgown and does not own the handkerchief found on the floor of Ratchett's compartment.
Greta Ohlsson is questioned next. Greta is supposedly the last person to see Cassetti (Ratchett) alive. She opened his door by mistake, thinking it was Mrs. Hubbard's door. Ratchett was inside reading. Before leaving Mrs. Hubbard's compartment, Mrs. Hubbard asked Greta to make sure the communicating door was bolted. Afterward, at approximately 10:55, she returned to her own compartment to sleep. Greta shares a compartment with Mary Debenham. Greta did not see Mary leave the room all night. Greta does not have a red dressing gown. She had not heard of the Armstrong case, but was most upset to hear about the kidnapping.
Pierre Michel is immediately called in to see about the conductor's uniform button Mrs. Hubbard found in her compartment after the murder. M. Bouc asks if Michel has any information, but he has none, his buttons are all in place. He is furious that they think he might be suspect and he calls in his colleague from the other car to corroborate his alibi. The colleague immediately confirms his story. The conductor is dismissed and Princess Dragomiroff is called in for questioning. The Princess tells Poirot that the night before she retired to bed immediately after dinner and read until 11 p.m. At about 12:45 she rang for her maid, Hildegarde Schmidt, who massaged her and read to her until she felt sleepy. She heard nothing unusual in that time. The Princess reveals that she was a close friend with the Armstrong family and their daughter, Sonia, was her goddaughter. She also tells Poirot that Mrs. Armstrong there is a younger Armstrong daughter, but the Princess has lost touch with her. The Princess has a black satin dressing gown. The Princes asks Poirot his name. When he tells her his name she responds, "Yes. I remember now. This is Destiny."
To keep the reader's interest and divert attention from the solution of the mystery, Christie intersperses evidence gathering with various interruptions and moments of action. Mrs. Hubbard is the primary instigator of diversion in Murder on The Orient Express, by interruption and distraction she attempts to mislead the reader and Poirot in the case. Mrs. Hubbard is Christie's premier puzzle maker, she twist's Christie's plot over and over again.
As later discovered, Mrs. Hubbard is the famous actress Linda Arden, grandmother of Daisy Armstrong. There is no doubt her acting talents help her confuse the murder suspects. Mrs. Hubbard's interruption in Chapter 5 is an example of her trickery. She provides a heart wrenching testimony, telling Poirot that the murderer was actually in her cabin and even gives Poirot real evidence, a Wagon Lit uniform button she found on the floor of her room. When Mrs. Hubbard is told that Ratchett is Cassetti, the known murderer of Daisy Armstrong, she is visibly excited. The emotional, boisterous and rather comical character Linda Arden creates makes the reader and Poirot assume her innocence. She, like Christie, diverts the reader from the truth because she is so believable.
Mrs. Hubbard is visibly shaken when she walks into the dining car, she can hardly articulate her words to Poirot because she is so excited. She weaves a horrific and wonderful story about the man that was actually in her compartment the night before. The detail and persistence of Mrs. Hubbard makes one assume that she could not be a suspect. Mrs. Hubbard only makes one mistake—the claim that she had to ask Greta Ohlsson to check to see if the communicating door was bolted because is was obscured by the sponge bag hanging from her doorknob. The bolt, later found to be a foot above her door handle, makes Mrs. Hubbard a certain suspect. This claim, which of course eventually proves her guilt, is the only clue against a seemingly infallible character.
Christie foreshadows the truth of Mrs. Hubbard's identity; she describes Mrs. Hubbard's behavior in acting terms. In Chapter 4, Mrs. Hubbard "paused to give dramatic emphasis to her words" and when she describes the Conductor's inability to find anyone in her room, "This seemed to Mrs. Hubbard to be a dramatic climax rather than an anticlimax." Mrs. Hubbard's actions are over "the top" and she even faints in Scene 14. Mrs. Hubbard makes formal entrances and exits to each of her "scenes" with Poirot. In Chapter 4 Mrs. Hubbard rushes into the scene exacerbated and frantic and sails out of the dining car triumphantly. Mrs. Hubbard's melodrama makes Poirot's discovery of her true identity, a famous actress, not at all surprising.
The presence of characters like Mrs. Hubbard makes Christie's mysteries more difficult to solve and follow. The reader wants to believe such carefully written and colorful characters, but, as in all of her books, the only character that can ever be trusted is the detective from the author's perspective. The thoughts and observations of Hercule Poirot are the only thoughts and observations to be trusted.