The Leavenworth Case (1878), subtitled A Lawyer's Story, is an American detective novel and the first novel by Anna Katharine Green. Set in New York City, it concerns the murder of a retired merchant, Horatio Leavenworth, in his New York mansion. The popular[1] novel introduced the detective Ebenezer Gryce, and was influential in the development of the detective novel. In her autobiography, Agatha Christie cited it as an influence on her own fiction.[2]