Disguised as a pacifist, Hannay travels from London to Glasgow to the Scottish Highlands and Islands in his search, which eventually ends in a spectacular climax above the battlefields of Europe.

It was here that the air photography, obtained by reconnaissance aircraft flying over the whole of enemy and occupied Europe, was analysed by Photographic Interpreters: the Intelligence produced from their reports influenced virtually every Allied operation planned and carried out during the war. An analytical mind, curiosity, the ability search for clues and recognise the unusual were essential qualities for the Interpreters and found in men and...