Christie was born into a wealthy upper-middle-class family in Torquay, Devon. She served in a Devon hospital during the First World War, tending to troops coming back from the trenches, before marrying and starting a family in London. She was initially an unsuccessful writer with six rejections, but this changed when The Mysterious Affair at Styles, featuring Hercule Poirot, was published in 1920. During the Second World War she worked as a pharmacy assistant at University College Hospital, London, during the Blitz and acquired a good knowledge of poisons which featured in many of her subsequent novels.