By the Pricking of My Thumbs By the Pricking of My Thumbs By The Pricking of My Thumbs is a work of detective fiction by Agatha Christie and first published in the UK by the Collins Crime Club in November 1968 and in the US by Dodd, Mead and Company later in the same year. The UK edition retailed at twenty-one shillings (21/-) and the US edition at $4.95. It features her detectives Tommy and Tuppence Beresford. Tommy and Tuppence were unusual in that they aged from novel to novel unlike Miss Marple and Hercule Poirot, whose age remained more or less the same from Christie's
Tommy and Tuppence flavour than the stories featuring the better known Christie characters. As they age, they are revealed to have raised three children – twins Deborah and Derek and an adopted daughter, Betty. Throughout the series they employ a man named Albert, who first appears as a lift boy who helps them in "The Secret Adversary". In "Partners in Crime," Albert becomes their hapless assistant at a private detective agency; and subsequently, as a now married pub owner, renders vital assistance to the pair in "N or M?."; by "Postern of Fate" he's their butler and has now been widowed. In "Postern