Agatha Christie is one of the most popular mystery writers of all times. The Mysterious Affair at Styles (1920) was her first detective novel. Her detective Hercule Poirot follows a confounding set of clues to discover who poisoned an old woman.

G. K. Chesterton, who co-founded the Detection Club with Sayers, created a priest-sleuth in this Father Brown series. Father Brown first appeared in The Innocence of Father Brown (1911). On the surface, Father Brown appears to be clumsy and naïve, but his clever mind, penetrating insight, careful observational skills, and deep understanding of human evil allow him to catch the criminal.

Sayers and thirteen other members of the Detection Club co-wrote The Floating Admiral (1932). Each writer wrote one chapter, and in the subse subsequent chapters, writers had to take into account characters and clues introduced.

Six members of the...