A detective story from Agatha Christie, featuring her iconic detective Hercule Poirot, first published in 1928.
Rich and unhappily married Ruth Kettering receives from her father a priceless and famous ruby, with a warning to never take it with her abroad lest she runs into danger. Unfortunately she embarks on Le Train Bleu towards the French Riviera with the ruby and is soon found strangled in her compartment. But Hercule Poirot was also on the train and begins to investigate the crime (with assistance from the French police) which, as always, is more than first appears.
Other characters include Katherine Grey, another passenger of the train, a young woman who received an unexpected inheritance and is travelling abroad for the first time; Ruth's estranged and ill-tempered husband, Derek Kettering; a cabaret dancer named Mirelle; the womanizing Comte de la Roche; the Marquis (a famous jewel thief who has never been identified); Ruth's millionaire father Rufus Van Aldin, desperate to find his daughter's murderer; and Van Aldin's secretary Major Knighton.
It was adapted for television in 2006 in an episode of Agatha Christie’s Poirot.
This novel provides examples of:
- The Alibi: Of course. The Comte has one. Derek Kettering doesn't.
- All Girls Want Bad Boys: Somewhat complicated for Katherine Grey, as she actually doesn't but simply isn't sure who is the Bad Boy. Somewhat surprisingly, they both turn out to be somewhat bad, but Derek ends up being the least bad and, having genuinely fallen for Katherine, resolves to change his ways so as to prove himself worthy of her.
- At Least I Admit It: Derek freely admits that he was only really interested in Ruth for her money, and defends himself by pointing out that he was always honest and above board with the woman herself about it.
- Betty and Veronica Switch: Katherine Grey finds herself in the midst of a burgeoning love triangle between the ill-tempered, selfish and disreputable but oddly charming murder suspect Derek Kettering and the stolid, reliable and dependable Major Knighton, both of whom come to develop feelings for her over the course of the story. Except they don't fill the roles you might expect; Kettering was a Gold Digger but turns out to have been honest in his intentions, innocent of murder and a better man than even he believed himself to be, while Knighton is a thief, con-artist and murderer.
- Bitch in Sheep's Clothing: Every man in the book sees right through the Comte. Not the women.
- Break the Haughty: Delivered by Poirot to Mirelle late in the story. Mirelle spends nearly the entire book flaunting her beauty and superiority, boasting that she can have any man she wants and that she always gets her way. She even goes so far as to incriminate Derek as petty revenge when he leaves her. After one intense interrogation session with Poirot, however, Mirelle is left a sobbing, screaming mess on the floor of her apartment. This is also the last time we see her in the rest of the novel.
- Busman's Holiday: Just one of several novels where poor Hercule Poirot winds up at a murder scene when he's on vacation.
- The Casino: Much of the action takes place in the gardens or gaming rooms of the casino at Monte Carlo.
- Cool Train: Le Train Bleu
, the luxury overnight service across France from Calais to Nice. - Creepy Crossdresser: Ada Mason is actually Kitty Kidd, an actress who specialized in male impersonation. Part of the murder plot involves her leaving the train in Lyons, disguised as a man.
- Fake Aristocrat: The 'Comte' de la Roche, who pretends to be an aristocrat but is actually the son of a grain merchant.
- The Fashionista: The first thing Katherine does upon inheriting her fortune is march into a fancy French atelier and order a cutting edge wardrobe. Understandable as she'd never had enough money for nice clothes before.
- Gold Digger:
- 'Chubby' Evans clearly only married Lady Tampling for her money. That said he keeps his side of the bargain by being a charming, faithful and not too extravagant husband. Mirelle, Derek Kettering's former mistress, is a much less sympathetic example.
- Kettering himself married Ruth in large part because of her money, though similarly to Evans he was at least honest with the lady herself about it, and points out that while he might not have been the best husband ever she also brought plenty of faults to the marriage.
- High-Class Glass: The Comte de la Roche makes a point of sticking a monocle in his eye when he's confronted by the French police (and Poirot) about the murder. Of course the joke here is that he's not really an aristocrat at all.
- Idle Rich: Most of the cast is either this, aspires to it or pretends to be it.
- I Never Said It Was Poison: Poirot wonders how Derek Kettering knows Ruth's rubies were stolen. He also wonders how Mirelle knows the time of death.
- Love Redeems: In the novel, Derek Kettering gradually finds himself trying to become a better person the deeper he falls in love with Katherine Grey.
- Marriage of Convenience: What Derek and Ruth Kettering had. Derek describes it as a perfectly fair bargain that failed due to faults on both sides.
- Murder the Hypotenuse: The murderer of Ruth Kettering attempts to pin the crime on Derek in no small part due to being jealous of him and Katherine.
- Nobility Marries Money: Kettering is a British nobleman whose fortune has dwindled, Ruth is an American heiress. Such matches were all over the place around the turn of the 20th century.
- Obfuscating Disability: The guy Poirot figures out to be the Marquis has a limp, but the Marquis is known to be in perfect health. Turns out, the limp is just pretence.
- Phantom Thief: The Marquis has this reputation.
- Pretty in Mink: Ruth Kettering's full length mink coat proves unexpectedly important.
- Punctuated! For! Emphasis!: Derek's reaction when the French police accuse him of going to the Blue Train to meet his wife."I—did—not—know—she—was—on—the—train," he explained, spacing his words elaborately, as though to someone dull of intellect.
- Sharp-Dressed Man: Poirot is of course famous for his dress sense, and the Comte is equally well dressed.
- Spanner in the Works: Knighton is undone because he left his cigarette case in Ruth Kettering's compartment, and then fell in love with Katherine Grey.
- Spoiled Brat: Our victim. Everybody but her loving father can see it. That said, she wasn't bad enough to count as an Asshole Victim.
- Thriller on the Express: Although only the murder and the initial investigation take place on the train.
- Til Murder Do Us Part: The fact that Ruth was about to divorce him and her death left him heir to her millions makes Derek the obvious suspect.
- Unexpected Inheritance: Katherine was a companion to an old lady in St. Mary Mead. It turns out that the old lady had a lot of money and saved it all, and left it all to Katherine on her death. Katherine is suddenly rich, which is why she's on the Blue Train.
- The Vamp: Mirelle.
- The Watson: Katherine Grey serves as this to Poirot in this novel. Somewhat unusual in that a lot of her thoughts and motivations are kept from the reader which allows for the also unusual reveal in Poirot's summation that she, too, correctly suspected Knighton.
- What Beautiful Eyes!: Just about every man in the book is entranced by Katherine's clear grey eyes.
- Also, comments on Poirot's bright green eyes.
