One of the first great spy novels, The Riddle of the Sands is set during the long suspicious years leading up to the First World War. In spite of good prospects in the Foreign Office, the sardonic civil servant Carruthers is finding it hard to endure the emptiness and boredom of his life in London. He reluctantly accepts an invitation from a college friend, Davies, the shyly intrepid yachtsman, and joins him on a sailing holiday in the Baltic. The story builds in excitement as Carruthers and Davies discover a German plot to invade England. Like much contemporary British spy fiction, The Riddle of the Sands reflects the Anglo-German rivalry of the early 20th century, and the intricacy of its conception and its lucid detail make it a classic of its genre.

With an Afterword by Ned Halley.