Brimming with heart-stopping action, The Riddle of the Sands is one the earliest spy novels. This spell-binding story is set in the period before the start of the First World War. A gem of the thriller genre! While on a sailing trip in the Baltic Sea, two young adventurers-turned-spies uncover a secret German plot to invade England. Written by Childers-who served in the Royal Navy during World War I-as a wake-up call to the British government to attend to its North Sea defenses, The Riddle of the Sands accomplished that task and has been considered a classic of espionage literature ever since, praised as much for its nautical action as for its suspenseful spycraft.