The Riddle of the Sands

Set against a backdrop of early 20th-century espionage, the story follows Carruthers, a Foreign Office official, who reluctantly joins an unexpected yachting trip with Davies in the German Frisian islands. What begins as a holiday soon turns into a suspenseful investigation as Davies unveils his suspicions about German military activities in the region. The novel intricately weaves themes of militarism and secrecy, making it a pioneering work in the espionage genre.