The Big Four

The Big Four is a mystery novel by the English writer Agatha Christie, published in Britain in January 1927 and in the United States later the same year.

It features Hercule Poirot, Captain Hastings and Inspector Japp, but it is not built like the other books about them: the plot began life as a dozen short stories published separately in The Sketch, and Christie and her brother-in-law Campbell Christie revised and joined them into a novel, mostly by writing new openings and endings to make the episodes run together. That origin is visible in the book's structure, which moves quickly from one incident to the next, and in its subject, since this is a tale of international conspiracy rather than a country-house murder. Christie wrote it in 1926, the year her mother died and her marriage to Archibald Christie broke down; the suggestion to assemble the existing stories into a book came from her brother-in-law, on the grounds that it would be less of a strain than writing something new. The novel is the only one of the early Poirot books in which the detective's opponents are organised, funded and prepared to attack him directly, and it opened a vein of spy fiction that Christie used again later.