The ABC Murders

"A madman, mon ami, is to be taken seriously. A madman is a very dangerous thing."

- Hercule Poirot. He was right.

1936 novel by Agatha Christie, often considered to be one of her best works. Hercule Poirot has received a letter after retirement, daring him to solve a case before a victim for every letter of the alphabet is killed.

Tropes featured include:
"Hercule Poirot:(after Hastings describes his ideal mystery) You have written a very pretty resume of nearly all the detective stories ever written. Hastings: Well, what would you order? Hercule Poirot: A very simple crime. A crime with no complications... very unimpassioned, very intime. Hastings: I can't see any excitement in that. Hercule Poirot: No, because there are no curiously twisted daggers, no blackmail, no emerald that is the stolen eye of a god... You have the melodramatic soul, Hastings."
 * Alliterative Name: The victims of the killer: Alice Ascher, Betty Barnard and Sir Carmichael Clarke.
 * Adaptation Decay: The 1966 film version emphasized comedy rather than mystery, and overall did not take its source material particularly seriously.
 * Berserk Button: Don't insult Hastings's combover.
 * Better to Die Than Be Killed: The murderer tries to commit suicide after The Reveal, but Poirot prevents this.
 * Calling Card: The murderer leaves a book of railway timetables at the scene of each murder. The book in question, naming all the stations in Britain in alphabetical order, is known as an ABC.
 * Chekhov's Gun: A rare case here, as while the Chekhov's Gun is not applicable in this book, it is relevant to a later Christie novel, Curtain. Within the opening pages of this novel, Hastings comments (once learning that Poirot dyes his hair)  In Curtain, the last Poirot mystery,
 * Connect the Deaths: Used as a red herring.
 * Criminal Mind Games: The killer at first appears this way.
 * Discussed Trope: By Poirot and Hastings, on murder mysteries:


 * Foolish Sibling, Responsible Sibling: Betty and Megan Barnard, respectively.
 * Foreshadowing: Poirot's description of the ideal mystery would end up being the plot of the novel Cards on the Table.
 * Genre Savvy: Poirot
 * Instant Death Knife: The fourth murder is committed in a cinema. The murderer leaves in the middle of the film, pretends to stumble, leans forward and stabs a random man, who dies instantly, without making a sound.
 * I Was Quite a Looker: When Poirot and Hastings see the dead body of the first victim, Alice Ascher, an elderly storekeeper, Poirot notes that she must have been beautiful when she was young. Hastings doubts it, but later, when they find her wedding photo, he sees that Poirot was right.
 * Malaproper: Poirot
 * Mistaken Nationality: Poirot gets mistaken for French, which annoys him greatly.
 * Murder by Mistake: 
 * Murder-Suicide: The murderer tries to commit suicide, but Poirot prevents it, because he doesn't believe that the murderer deserves an easy death.
 * Napoleon Delusion: referenced by Poirot when speaking of the killer.
 * Needle in a Stack of Needles:
 * Never One Murder: Lampshaded at the beginning when Poirot and Hastings talk about murder mysteries, and Hastings says that it's good if a story has more than one murder, because otherwise it could get boring.
 * Never Speak Ill of the Dead: The page quote, but subverted with the line that comes after.
 * Poirot Speak
 * Red Herring:
 * Serial Killer: Could arguably be considered a subversion. The psychology of serial killers is a Discussed Trope throughout the novel, especially in The Summation.
 * Serial Killings, Specific Target
 * Twist Ending
 * Theme Serial Killer: Subverted in that
 * The Watson: Captain Hastings
 * The Watson: Captain Hastings