Dumb Witness

Dumb Witness is a detective fiction novel by British writer Agatha Christie, first published in the UK by the Collins Crime Club on July 5 1937 and in the US by Dodd, Mead and Company later in the same year under the title of Poirot Loses a Client. The UK edition retailed at seven shillings and sixpence (7/6) and the US edition at $2.00.

The book features the Belgian detective Hercule Poirot and is the second to last Poirot novel (the last being 1975's Curtain: Poirot's Last Case) to be published that features Hastings as narrator.

Dumb Witness was based on a short story entitled The Incident of the Dog's Ball. This short story was lost for many years but found by the authoress's daughter in a crate of her personal effects, in 2004. The Incident of the Dog's Ball was published in Britain in September 2009 in John Curran's Agatha Christie's Secret Notebooks: Fifty Years Of Mysteries. The short story was also published by The Strand Magazine in their tenth anniversary issue.