"The Murder of Roger Ackroyd" really turns a new trick in detective fiction, surely a difficult enough achievement "with the competition so strong." Most writers of detective stories develop their own special detectives, following the lead of the famous. Agatha Christie's pet detective is Hercule Poirot….

Poirot is merely one factor in a tale so ingeniously constructed, so dextrously plotted as to warrant our complete admiration. It is unfortunate for us that we may not indicate here the most original element in Miss Christie's planning of the story. But that would be treachery to the author, and the reader has no right to be too well informed in advance….

Suffice it to say that Miss Christie's dedication of the book is to one "who likes an orthodox detective story, murder, inquest, and suspicion falling on every one in turn!" So she set herself to write such an orthodox...