Dame Agatha Mary Clarissa Christie, (1890 - 1976) was an English crime novelist, short story writer, and playwright. She also wrote six romances under the name Mary Westmacott, but she is best known for the 66 detective novels and 14 short story collections she wrote under her own name, most of which revolve around the investigations of such characters as Hercule Poirot, Miss Jane Marple and Tommy and Tuppence. She also wrote the world's longest-running play, The Mousetrap. Born into a wealthy upper-middle-class family in Torquay, Devon, Christie served in a hospital during the First World War, before marrying and starting a family in London. She was initially unsuccessful at getting her work published; but in 1920 The Bodley Head press published her novel The Mysterious Affair at Styles, featuring the character of Poirot. This launched her literary career. In this book: The Mysterious Affair at Styles, 1920 The Secret Adversary, 1922