The Thirty-Nine Steps is one of the earliest examples of the '"man-on-the-run" thriller archetype subsequently adopted by film makers as a much-used plot device. In The Thirty-Nine Steps, Buchan holds up Richard Hannay as an example to his readers of an ordinary man who puts his country's interests before his own safety. The story was a great success with the men in the First World War trenches. One soldier wrote to Buchan, "The story is greatly appreciated in the midst of mud and rain and shells, and all that could make trench life depressing."[9]
Hannay continued his adventures in four subsequent books. Two were set during the war, when he continued his undercover work against the Germans and their allies the Turks in Greenmantle (1916) and Mr Standfast (1919). The other two stories, The Three Hostages (1924) and The Island of Sheep (1936) were set in the postwar period, when Hannay's opponents were criminal gangs.
