A crime novel best known by its Hitchcock adaptation

John Buchan's 1915 novel, The Thirty-Nine Steps, is today best known by its cinematic incarnation as Hitchcock's The 39 Steps, and with good reason: The brief novel is by Buchan's admission nothing more than an entertainment that lies just this side of the improbable, and that's putting it mildly! The narrator - who gives temporary shelter to a neighbor who's loosely involved w/ some sort of anarchist plot to drawn the UK into war - becomes an unwitting subject, pursued by both the anarchists and the British police. He escapes by train, on foot, crawling across bridges, stealing an expensive chauffeured car that he drives into a crevice, and so forth - in other words, nothing that's likely to happen to anyone let alone to this one person resourceful person. But the events seem almost to be scripted for movies - and in that regard decades ahead of its time; what we can only barely accept in a novel becomes that much more real when enacted on screen; we're that much less likely to say, no, this couldn't happen, when we're watching it happen. This novel is not only the source for Hitchcock's 39 but also seems to be inspirational for his entire cinematic style: Think of Cary Grant in North by Northwest forced to bid in an antiques auction, and compare with Buchan's narrator forced by circumstance to lecture a crowd of 500 on Australian politics, about which he knows nothing - and you'll see the foundation here of H's insouciant heroes, amateurs forced into action. I'm curious as to whether the revelation of the meaning of 39 steps is the same in both novel and film; the big reveal in H's movie is one of the great moments in crime/mystery movies, and I suspect Hitchcock not Buchan might have been the source.