The country mansion Chimneys, the setting of Christie’s earlier novel The Secret of Chimneys , has been rented out by Lord and Lady Coote, who are hosting a weekend party. One of the guests, Gerry Wade, has a habit of oversleeping, so his friends decide to play a prank on him by surrounding his bed with eight alarm clocks. Naturally, the next morning he is found murdered in his bed, with one of the alarm clocks missing—leaving only seven dials in his bedroom.

Eileen “Bundle” Caterham, the daughter of the owner of Chimneys and one of the characters in The Secret of Chimneys , joins Superintendent Battle in investigating the crime. Her doggedness leads her to a scheme of grand industrial espionage—and a mysterious secret society.

Unlike The Secret of Chimneys , The Seven Dials Mystery met with a middling reception, with contemporary reviewers complaining about a lack of the vivacity that made Secret so charming, an almost-unguessable solution to the mystery, and an unlikely ending to the novel. Christie wrote it in what she called her “plutocratic era,” when she favored easily and quickly written stories that could be sold for very large sums to American publishers.