This was the first and best known of a series of adventure novels featuring a Scot named Richard Hannay. Buchan said he filled them with improbable events that readers could only just believe might happen. I’m reminded of The Adventures of Brisco County Jr, a television series whose writing staff said they aimed for just under over the top.
The novel opens with Hannay living in London after having recently made his fortune in South Africa. He’s rather bored until he finds himself framed for murder and on the run from both the police and mysterious foreign spies. This alleviates his boredom wonderfully.
The novel is fast-moving, brief, and occasionally cynical and funny, and is supposed to have been one of the first to use the now-commonplace plot device of a hero on the run from everybody. There’s a lot stuffed into just over 40,000 words, including some (fortunately very brief) examples of the racism common to the era. It’s a reasonable amount of fun but not terribly memorable despite its enduring popularity.
The title was reportedly inspired by something Buchan’s six-year-old daughter said while he was recuperating from an illness in a seaside nursing home. She had just learned to count and one day happily reported that there were 39 steps on the stairway leading down to the beach.
Like his protagonist, Buchan was a Scot who’d spent time in southern Africa, though he’d been there as a government official rather than a seeker of fortune. Buchan wrote a great deal besides fiction, including propaganda for the British government during World War I. He was later elected to Parliament to represent the Combined Scottish Universities, and after being created the first Baron Tweedsmuir he spent his last years (1935-1940) as Royal Governor-General of Canada.
The book is out of copyright in the U.S. and can be found on line, for example at Project Gutenberg.