From the author of The Thirty Nine Steps which has been made and remade into films, one expects some plot turns and twists. This tale does not disappoint.

Geography is covered in vast sweeps, the opponent characters somewhat simplified verging on stereotyping not unusual for the era. The good guys treated to some of the best characterization I've read. It is a short read, but I finished anticipating the reactions of characters as I felt I knew them so well. But a romp through the vast sweep of The Great War, complete with terms and concepts circa the era and interesting for the either lexicographer or the social scientist (armchair variety like myself).

This book has a scope too vast for the economy of modern film, as one rarely drops in the Eastern Front of WWI as backdrop to an excellent spy novel.

The second in a series of wartime spy novels in the best British genre, unprofessional good effort winning against all odds and a total lack of modern cynicism. Quite refreshing for that alone.