Mr. Standfast (audiobook)

This is the third of Buchan's Richard Hannay novels, following The Thirty-nine Steps and Greenmantle. Set, like Greenmantle, during World War I, it deals Brigadier-General Hannay's recall from the Western Front, to engage in espionage, and forced (much to his chagrin) to pose as a pacifist. He becomes a South African conscientious objector, using the name Cornelius Brand. Under the orders of his spymaster, Sir Walter Bullivant, he travels in the book through England to Scotland, back to the Western Front, and ultimately, for the book's denouement, into the Alps.