The thirty-nine steps ; The power-house

The Thirty-Nine Steps (1915) introduces Richard Hannay, the original gentleman-hero of spy thrillers and a forerunner of James Bond. This tale of intrigue and treachery pits Hannay against not only a German spy ring but also the British police, who wrongly suspect him of murder.
Hunted relentlessly, he flees to Scotland and races against time to expose a plot that would drive Britain to the brink of war. His success rests on the whereabouts of the mysterious thirty-nine steps..
The Power-House (1913) features another of Buchans most popular protagonists, Sir Edward Leithan, on a desperate mission to uncover a sinister plot to destroy western civilization.