‘So we do it for real.’

As it happens there was a real progenitor for John Macnab: Captain James Brander Dunbar, born in 1875, the same year as Buchan. An upper-class, ex-Boer War eccentric, spy, crack shot and terrific fisherman, flouter of convention while being a Tory to the core – his successful wager with Lord Abinger that he could poach a stag from his estate had become legendary.

If Brander sounds like one of Buchan’s high-achieving, stirring Tory heroes, there’s a reason: Buchan’s key characters, however dashing and improbably multi-talented, were always drawn from experience. When Buchan writes of a winter crossing of the Alps, stirring up revolution in the Balkans, using a trick of the wind to mis-direct deer, giving a hustings speech as a nervous Tory candidate (a recurrent scene), the burdens of high office and dyspepsia, crawling through Highland estates with a ghillie and a gun, teasing salmon with a dry-fly, he had either done it himself or knew well people who had.

This gives his writing authority, passion and conviction, however improbable the tale. And though the social and political attitudes of his times have vanished, Buchan’s writing still reads well, for his model was Stevenson, not Scott. The prose remains clear, stripped and yet stirring, combining pace, reflection and uncluttered, characterful narration. Though socially ambitious, Buchan’s interest in, attention to and respect for ghillies and ‘tinklers’ and ‘other ranks’ makes for a wide range of encounters in John Macnab, most memorably with ‘Fish Benjie’ whose name closes the tale. The various Scots of the book – Lallans, Doric and Highland – are parts of a remarkable linguistic patchwork, happily embracing inter-textuality and much quotation from classics, folk-tale, Scott, the Bible, Bunyan.

John Macnab stands apart fom the Richard Hannay novels. It is an adventure, not a thriller. There is no great Jewish-anarchist-Bolshevik conspiracy, no great cause into which the heroes are reluctantly drawn. The nearest we come to a baddie is Johnson Claybody, the heir of a self-made millionaire, whose crime is his pompous priggishness, self-importance, materialism and an entire absence of humour or romance.

It also has the most interesting female character in Buchan’s fiction in Janet Raden, daughter of Lord Raden, an old-aristocracy Highland landowner. Like all Buchan’s good women, she is essentially a chap, at home on the hill, wearing breeches, adept at fishing and stalking, with ‘the eyes of an adorable boy’. (Just as Sandy Arbuthnot, the most romantic of Buchan’s heroes, is repeatedly described as having ‘the eyes of a girl’.) Not only does Archie Roylance (the Fourth Macnab in the way George Martin was the Fifth Beatle) fall in love with her in an almost Wodehousian tongue-tied way, but she utters the most unexpected and striking and perhaps deeply-felt notions in the book. She argues passionately with Archie that the old aristocracy are dying, are losing their place and possessions, because they deserve to. Her phrases jump out, startling Archie and ourselves equally: ‘We’ve long ago lost our justification’; ‘Nobody in the world today has a right to anything he can’t justify’. When Archie says this sounds like Bolshevik talk, she retorts it probably is.

Though a Tory to the core, Buchan was an odd and peculiarly Scottish one. Here he argues – and no one, least of all Archie, contradicts Janet – a radical meritocracy. The status quo itself is no justification. Buchan and his characters consistently approve the self-creating nature of American and Colonial life, the lack of ‘side’ and social inhibition.

John Macnab is the sunniest of Buchan’s fictions, as Sick Heart River is the most dark and deeply felt. Both take Sir Edward Leithen as the central character, the one Buchan wryly acknowledged as being closest to himself: a dry, if successful, over-worked, assiduous, sober lawyer. Along with his friends Palliser-Yates (something big in the City, the least rendered character) and Lord Lamancha (Cabinet Minister and crack shot) he suffers from ‘taedium vitae’. Work and play have lost their savour. ‘I daresay it’s due somehow to the war’ – and the Great War is the key backdrop to this tale, as it was in Buchan’s life. They have got too deeply into their comfort zone, and, lacking a war or crisis, their only solution is to generate a challenge and risk failure and ridicule. Turning their backs on analysis and the ‘talking cure’, they take up the Stalking Cure.

This theme of comfort zone, staleness and cure by self-created adventure (which can include falling in love) is the heart of John Macnab, and it remains lasting and universal. We may live in an age of anxiety and insecurity; it is equally true that we suffer at times from staleness, predictability and living too long inside our comfort zone. That was what drew Mal Duff to the book, for climbing arises more from a terror of boredom than any self-destructive tendency.

A comic outlook does not come naturally to the son of a Free Kirk minister. His fictions can be dashing, stirring, dramatic, but they are always high-minded and Presbyterian at heart. But John Macnab is a comedy-adventure, full of flicks of wit, mischief, mockery and mickey-taking (his portrait of the newly-arrived Lady Claybody is quite inspired); like all good comedy it ends (without giving too much away) in an engagement, a feast, self-knowledge (‘I think we have all made fools of ourselves’), forgiveness and healing.

We never did our John Macnab ploy, of course, though there was a certain amount of, shall I say, reconnaissance and research. Mal kept going on expeditions, I was ill, we both got older, and one day I realised I was better fitted to write it than do it. So I wrote The Return of John Macnab, with somewhat less elevated protagonists, very different politics, and a Janet Raden character that ran away with the book, the ploy and several hearts.