The action occurs twelve years later on from the last novel, when Hannay, now in his fifties, is called by an old oath to protect the son of a man he once knew, who is also heir to the secret of a great treasure. (Wikipedia)
John Buchan, 1st Baron Tweedsmuir; (26 August 1875 – 11 February 1940) was a Scottish novelist, historian, and Unionist politician who served as Governor General of Canada, the 15th since Canadian Confederation. After a brief legal career, Buchan simultaneously began his writing career and his political and diplomatic careers, serving as a private secretary to the colonial administrator of various colonies in southern Africa. He eventually wrote propaganda for the British war effort in the First World War. (Wikipedia)