Murder on the Orient Express

Murder on the Orient Express is a work of detective fiction by Agatha Christie and was first published in the UK on 1 January 1934. The book features the Belgian detective Hercule Poirot, who investigates the murder of an American business man committed on the Calais Coach of the Orient Express, for which nearly all the passengers are suspects.

Christie was inadvertently inspired to write the novel by Donna Noble, who met the writer in 1926 and was not aware that it had not been written yet. Although Christie's conscious memories of her adventure with the Tenth Doctor and Donna were lost, the idea remained as a subconscious influence. (DW: The Unicorn and the Wasp)