'He told me some queer things that explained a lot that had puzzled me; things that happened in the Balkan War, how one state suddenly came out on top, why alliances were made and broken, why certain men disappeared, and where the sinews of war came from.' Although written in 1915, this taut, superbly written thriller retains much of its original verve through the sheer perspicacity of the mind that created it. It is far more difficult for a thriller to maintain an ongoing contemporary relevancy than it is for most other genres. Crime fiction can stay true to its period, romance feeds on the broken hearts, not the detail, and chick-lit needs only dummies to buy it, a breed in no danger of dying out.

But for thrillers, particularly geopolitical ones, history changes perspective and the well-informed can come to look ridiculous (Tom Clancy). Not so with The 39 Steps. Richard Hannay, a former South African miner, becomes that now clichéd invention: the amateur caught up in a game he doesn't understand. In Hannay's case it's the whys and wherefores of a body in his London apartment and a pre-WW1 German spy plot. As Hannay struggles to retain his freedom and discover the truth, the reader enjoys the type of enjoyable, superbly paced literary yarn for which the word 'rollicking' was devised. Along the way the hero is transformed from establishment figure to pursued rogue, with the security forces coming in for a fair amount of implicit criticism at a time when Have I Got News For You? had not yet made such carping so predictably mundane.

While some might, and have, taken issue with the amount of luck that Hannay encounters in his quest, this is to somewhat miss the point: such things do happen. How 'lucky' were the 9/11 hijackers to find a flying school that was willing to teach people who didn't want to learn how to take-off or land? Moreover, the entire brilliant enterprise and architecture of The 39 Steps is infused with and underwritten by John Buchan's insider's grasp of what really happens in such worlds.

With a career that included war-time journalism, soldiering, spying and politics, Buchan writes convincingly of the apparatus and methodology of this still largely hidden world. His oeuvre changed the way people thought of thrilling literary fiction (his most obvious successor was Graham Greene) and given the fame of the book through several filmic adaptations, this is as strong a point as any to cross the bridge into Buchan's writing.

Further reading: The Power-House (1916) tells of a young lawyer fleeing murderous establishment figures; Greenmantle (1916) is akin to The 39 Steps, transferred to a German setting.

View the complete list of the 100 Best Scottish Books.

The 39 Steps: Alfred Hitchcock Film Trailer - Robert Donat, Madeleine Carroll (1935)