"The Mysterious Affair at Styles" is a classic detective novel written by Agatha Christie and published in 1920. It is notable for being the first novel to feature Christie's iconic fictional detective, Hercule Poirot. The story is set in England during World War I and revolves around the wealthy Inglethorp family, who reside in the country estate of Styles. When the family matriarch, Emily Inglethorp, dies under suspicious circumstances, Poirot is called upon to investigate.The novel is a classic example of a "locked-room mystery," where the crime occurs in a closed environment with a...