Greenmantle

This time Richard Hannay, the hero of Buchan's secret-service series, is on the front lines during World War I and is commanding a battalion when he is called in to do more for the Empire. The plot involves Muslims and more complications than he at first anticipates.

Alfred Hitchcock adapted John Buchan's most famous book The Thirty-Nine Steps for screen, although professed to preferring Greenmantle as a book. Three other Richard Hannay novels followed—Mr. Standfast, The Three Hostages, and The Island of Sleep. The grandson of John Buchan, James Buchan's books include Crowded with Genius, Frozen Desire, and The Persian Bridge.