Anna the Adventuress is a novel written by Phillips Oppenheim. Two identical sisters are able to switch places, leading to a series of unfortunate incidents.
E. Phillips Oppenheim (1866-1946) was the earliest writer of spy fiction as understood today, inventing the "rogue male" school of adventure thrillers and writing over 150 novels of all sorts. Nicholas Goade, Detective is a collection of short mysteries.
