Making his way past the commotion in front of Mrs. Hubbard’s cabin, Poirot finds the knife in Mrs. Hubbard’s bag. It’s a cheap knife in the oriental style which Dr. Constantine says could have been used for any of Ratchett’s twelve wounds. Poirot says in mock-weariness, “Two people decided to stab M. Ratchett last night. It is too much of a good thing that both of them should select the same weapon."
The discovery of the murder weapon, which in another novel might be the crux of the mystery, doesn’t seem to have a huge impact on the case. Poirot’s comment reflects his running theory that the crime was committed by at least two people, but two people using the same weapon seems convenient to the point of absurdity.
Poirot seems dismissive of the murder weapon and instead removes the sponge-bag from the door handle to Ratchett’s compartment. He notices the bolt is above the handle. When M. Bouc observes his fiddling with the door, Poirot says cryptically, “The same point does not strike you? No, evidently not.”
Mrs. Hubbard had previously told Poirot that she couldn’t see whether the door was locked because her bag was blocking the bolt. But the bolt is above the handle, so Mrs. Hubbard was mistaken or lying.
Poirot tries the door to Ratchett’s cabin and can’t get through, as they had locked the door on the other side. Poirot takes pains to soothe Mrs. Hubbard and discusses the door between Ratchett’s cabin and hers. He suggests that Greta, when she checked the bolt, may have thought it locked on Mrs. Hubbard’s side when it was only locked on Ratchett’s side.
Since the doors to adjoining compartments can be locked on either side, in which case they can’t be used, Greta may have thought the door was locked when it was actually open. This implies that someone in Ratchett’s cabin may actually have been able to escape through Mrs. Hubbard’s cabin and into the hallway.
Mrs. Hubbard describes more of her journey, expressing displeasure with Istanbul as a “tumble-down city.” Poirot takes the opportunity to search her bags, with her permission, which takes longer because he has to look through pictures of Mrs. Hubbard’s children.
Even distraught, Mrs. Hubbard can’t help but condescending to the ancient, beautiful city of Istanbul in her particularly American way. Poirot looks through pictures of her children as a way to keep Mrs. Hubbard calm while he searches his luggage.