Tommy and Tuppence Beresford are among the lesser-known creations of which crime writer?

Tommy and Tuppence are two fictional detectives created by Agatha Christie (1890-1976). The husband and wife team, full names Thomas and Prudence Beresford, first appeared in 'The Secret Adversary' (1922). Tuppence is a charismatic, impulsive, and intuitive woman, whereas her husband Tommy is less imaginative and likes to focus on the facts.

In 'The Secret Adversary', Tommy and Tuppence were friends in their early twenties. Unlike Christie's well-known characters Miss Marple and Poirot, the Beresford's age in time with the real world. Throughout the series, they marry and raise three children, twins Deborah and Derek and an adopted daughter, Betty. By the final book, 'Postern of Fate' (1973), Tommy and Tuppence are in their seventies.

In the first book, Tommy and Tuppence start up a business called 'The Young Adventurers' and are soon hired to search for a survivor of the sinking of the RMS Lusitania. Following the successful conclusion of their first case, they are hired by a government intelligence agency to solve a case. Despite closing the business to focus on raising a family, the Beresfords find themselves recruited by the British intelligence during World War Two. Their final mystery case takes place when they find an old book containing a coded message in their newly purchased retirement property.

The Tommy and Tuppence books have been adapted several times for radio and television.