In Agatha Christie's mystery novels, several characters cross over different sagas, creating a fictional universe in which most of her stories are set. This article has one table to summarize the novels with characters who occur in other Christie novels; the table is titled Crossovers by Christie. There is brief mention of characters crossing over in adaptations of the novels. Her publications, both novels and short stories, are then listed by main detective, in order of publication. Some stories or novels authorised by the estate of Agatha Christie, using the characters she created, and written long after Agatha Christie died, are included in the lists.
Her novels under the pen name Mary Westmacott and her nonfiction books are not covered in this article.
One notable example of characters from one novel appearing in another is the novel The Pale Horse, which featured no fewer than five cross-over characters: Ariadne Oliver, Major Despard and his wife Rhoda (all had previously appeared in the Poirot mystery Cards on the Table; although Mrs Oliver appeared in numerous later Poirot mysteries) and the Rev and Mrs Dane Calthrop (who were seen in the Miss Marple mystery The Moving Finger).
List of cross-overs
Crossovers by Christie
Crossovers in media adaptations of novels or short stories
Outside of stories by Christie herself, three media adaptations of her works have featured crossovers involving Miss Marple which Christie herself never wrote; two of the three aired many decades after her death:
List of novels & short stories by featured detective
Hercule Poirot
Miss Marple
Mr Satterthwaite
Parker Pyne
Superintendent Battle
Tommy and Tuppence
Colonel Race
Trivia
- Agatha Christie herself exists in her fictional universe, as she is mentioned by a character in the Miss Marple novel The Body in the Library.
- In The Labours of Hercules, a character imagines a friendship between the mother of Hercule Poirot and his supposed brother Achille, and the mother of Sherlock and Mycroft Holmes, perhaps implying that Arthur Conan Doyle's Sherlock Holmes adventures are set in the same universe.
- The collection Partners in Crime may create an inconsistency: in it, Tommy and Tuppence mimick a series of famous fictional detectives of the period, including Sherlock Holmes and Hercule Poirot, thus implying that they are fictional in the universe. Similarly, in The Clocks, Poirot takes The Adventures of Sherlock Holmes down from a bookshelf, and utters the word "Maître!" while looking at the book. The narrator asks if it is Sherlock Holmes who is the object of his admiration, to which he responds: "Ah, non, non, not Sherlock Holmes! It is the author, Sir Arthur Conan Doyle, that I salute. These tales of Sherlock Holmes are in reality far-fetched, full of fallacies and most artificially contrived. But the art of the writing - ah, that is entirely different. The pleasure of the language, the creation above all of that magnificent character Dr. Watson. Ah, that was indeed a triumph."
References