Much later in the evening (after Poirot’s conversation with Simon), Poirot knocks on a cabin door. A voice tells him to come in—Jacqueline is sitting with a stewardess. Jacqueline asks if the stewardess can be dismissed, and Poirot nods, so she leaves. Poirot sits, and there’s a long period of silence.
Christie skips Simon’s confession because it would likely have been similar to Jacqueline’s. Poirot seems to have more respect for Jacqueline because she, like him, is cunning, whereas Poirot clearly finds Simon foolish and unworthy of respect.
Then Jacqueline says “Well, it is all over! You were too clever for us, Monsieur Poirot.’” Poirot sighs and silently acknowledges her comment. Jacqueline says Poirot still lacks solid proof—he has nothing that would convince a jury—but the problem was that Simon was such a “bad loser” that he confessed to everything when Poirot grilled him earlier. Poirot calls her a “good loser,” causing Jacqueline to laugh strangely. She asks if Poirot ever considered letting her off the hook, but he says no. Jacqueline says it’s probably for the best—she might even kill again, now that she knows how easy it is. She notes how a murderer begins to feel that they are the only person in the world who matters.
Jacqueline has kept her dark sense of humor, even after being caught in the act of murder. Throughout the novel, it turns out that she was actually honest with Poirot most of the time—the majority of what she said was true in some way, though she frequently used the truth in a way that could mislead. Though like Tim, Jacqueline seems to show some remorse for her crime, orchestrating a murder is a much graver offense than stealing some jewelry, hence why Poirot doesn’t let her off the hook.
Jacqueline asks Poirot if he knew what she was plotting during their earlier conversation in Assuan when he told her not to open her heart to evil. Poirot shakes his head, saying he only knew that his words were true. Jacqueline acknowledges that maybe she should have listened to Poirot’s advice. She asks if he’d like to hear the story from the beginning, and he says he would if she cares to tell.
Jacqueline fits the archetype of a villain who has nothing left to lose, so she explains everything. This sort of detailed convention is a convenient device for mystery stories, one that often allows them to have more satisfying endings.
Jacqueline begins by simply saying she and Simon were in love. Poirot asks if that was enough for her but not for Simon; Jacqueline admits there’s some truth in the statement. But she argues that there’s more to Simon: he has a childlike desire for all the nice things in life he’s been denied but that money would help him get. He didn’t want to marry rich, especially after he met Jacqueline. Still the two of them couldn’t see when they’d get married—Simon actually lost his job in the city when he got caught trying to “do something smart over money.” Jacqueline believes that naïve Simon just thought that’s how things worked in London, and that he wasn’t doing anything particularly wrong.
There might be reason to be suspicious of Jacqueline’s account here: it is self-serving and seems to deliberately paint her as a bystander who was drawn into Simon’s plot. Still, many of the details line up with what has already been revealed about Simon’s life and his personality.
Jacqueline says that Linnet really was her best friend, even as she envied her. At first, she really did only plan on getting Simon a job (which they were celebrating when Poirot saw them at Chez Ma Tane). Jacqueline insists that it was Linnet herself who started going after Simon first, not even trying to hide it.
Jacqueline is again going for sympathy, though that doesn’t necessarily mean that she’s lying. The book leaves some ambiguity to continue building suspense.
Jacqueline says Simon didn’t really like Linnet because he didn’t like bossy women, but he did like the thought of her money. Still, he turned down the idea of marrying her, even after Jacqueline suggested it. According to Jacqueline, it was Simon who first got the idea of murder, starting one day when he had a fantasy about marrying Linnet and having her die within a year. He kept harping on the idea, even reading about arsenic one day. Jacqueline realized then that Simon was serious about the idea—but she knew he was too simple to pull it off on his own. Jacqueline claims she really only got involved for Simon’s own good, to look after him. Poirot has no doubt that this actually was Jacqueline’s motive.
There seems to be at least one lie in Jacqueline’s story: she claims Simon doesn’t like bossy women—but arguably, Jacqueline herself is bossy, given that she took over his whole plot against Linnet in order to plan it better. This is the best evidence that she might be fooling Poirot. Then again, the narration specifically indicates that Poirot has no doubt about Jacqueline’s motives—and Poirot is usually right, particularly given how he just outsmarted Jacqueline.
Jacqueline details her efforts to work out the plan. She worked out the details so that if anything went wrong, the blame would fall on her instead of Simon. While most of the crime went out as planned, the J written in Linnet’s blood was improvisation on Simon’s part. Louise, however, disrupted their perfect plan.
Jacqueline’s intense love for Simon caused her to unimaginable things, which suggests that romantic love can turn obsessive rather healthy and has the potential to bring out the worst in people. Simon also proves his incompetence again—he couldn’t resist the urge to add a personal touch to the plan by writing the J.
Jacqueline tells Poirot that what happened with Louise is pretty much exactly what he’d expect. Jacqueline adds that she found it scary, actually, how easy it was for her to murder Louise. Killing the witness Mrs. Otterbourne was a split-second decision but simple enough to carry out, given she had no alternative.
This part is shocking because until this moment, Jacqueline’s story was presenting her in a relatively sympathetic way. It recalls the conversation Poirot had earlier with Mrs. Allerton where he suggested that almost everybody was capable of murder.
Jacqueline tells Poirot not to worry about her. If the plan had gone off perfectly, she and Simon might’ve lived happily ever after, but now she’s prepared to face the consequences. She assures Poirot that, while the stewardess was “in attendance to see I don’t hang myself or swallow a miraculous capsule of prussic acid as people always do in books,” she has no intention of doing those things. She recalls an earlier conversation where she told Poirot she must follow her star but Poirot warned her it might be a bad one. As he goes out to the deck, Poirot hears Jacqueline’s laughter ringing in his ears.
The moral of the story is essentially that all of this could’ve been avoided if Jacqueline just listened to Poirot’s earlier advice. Jacqueline’s laughter is significant, as it further suggests that she’s emotionally unstable and perhaps shouldn’t be trusted. Her reference to what characters do in books is one of many metafictional references that Agatha Christie makes to other mystery stories, often to contrast her work with theirs (letting the reader know not to expect the same old tricks), but also to situate her writing within the same genre.