First published in 1915, "The Double Traitor" is one of the greatest First World War spy novels. In the thrilling plot the main focus remains on the European political intrigues. Edward Phillips Oppenheim (1866-1946) was an internationally renowned author of mystery and espionage thrillers. His novels and short stories have all the elements of blood-racing adventure and intrigue and are precursors of modern-day spy fictions.

The setting of "The Double Traitor" is the years prior to the outbreak of World War I. It is a time when Germany is outwardly preparing for war but Britain continues to believe it is invincible and that no one would challenge her. A vast German spy network flourishes in England, often in plain view. The main character is Francis Norgate, an aspiring British diplomat who falls in disfavor with his superiors for defending a woman while stationed in Berlin. The resulting scandal causes Norgate to be recalled. On the way home, he meets a German gentleman, Selingman, who claims to be a crockery salesman. But, Selingman is not what he appears to be. Disillusioned by the English government, Norgate allows himself to be recruited by Selingman...