Greenmantle

In late 1915, Richard Hannay, now a major recovering from wounds received at the Battle of Loos, is called to the Foreign Office and given a desperate mission. Germany is believed to be preparing a religious uprising across the Muslim world, centred on a mysterious prophet known as Greenmantle. With three companions, among them the American John S. Blenkiron and the old Boer hunter Peter Pienaar, Hannay crosses wartime Germany in disguise to reach Constantinople and the besieged Ottoman fortress of Erzurum.

John Buchan published this sequel to The Thirty-Nine Steps in 1916, while working for Britain's wartime propaganda and intelligence services, and it drew on real German efforts to rouse the Muslim world against Britain. Its picture of the East reflects the attitudes of a British imperial writer, but as a thriller it is fast and inventive.