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.