- ISBN: 9780812966145 | 0812966147
- Cover: Paperback
- Copyright: 12/10/2002
While on a sailing trip in the Baltic Sea, two young adventurers-turned-spies uncover a secret German plot to invade England. Written by Childerswho served in the Royal Navy during World War Ias a wake-up call to the British government to attend to its North Sea defenses,The Riddle of the Sandsaccomplished 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.