A long extended farce, featuring the sort-of dynamic duo Warnford and Marden. Warnford has been cashiered from the British Army for important documents going missing on his watch, and Marden robs safes for a living. Marden fails to rob Warnford's safe and a beautiful friendship is instantly born, which segues immediately into the both of them going up against Hitler's finest in the UK in the year before the war. Disgraced officer and cat burglar they may be, they aren't unpatriotic.

Faint but pursuing, M.I.5 operative Tommy Hambledon is trying to figure out just who these two entrepreneurial amateur spies are who keep leaving him billet-doux all over southern England in the form of German spies, tied up neatly and left in places convenient for Hambledon to retrieve.