When the Hitchcock film version, The 39 Steps, starring Robert Donat as Hannay, came out in 1935, the time period was moved forward twenty years, but the plot still featured an innocent man getting drawn into a spy plot to uncover British military secrets and being forced to go on the run.
In the course of a very busy life, Buchan (1875-1940), the son of a Scottish minister, was the author of more than thirty works of fiction, a respected historian, a member of Parliament, and a diplomat who spent his final four years as Governor General of Canada. He is best remembered today for his thrillers, of which The Thirty-Nine Steps, published in 1915, is the first of five books featuring Richard Hannay as hero. Buchan came up with the plot and the title while recovering from an ulcer at a sanitarium, when his young daughter counted the steps leading from the building down to the beach (there were actually 78, but he decided 39 sounded better in a title). When the Hitchcock film version, The 39 Steps, starring Robert Donat as Hannay, came out in 1935, the time period was moved forward twenty years, but the plot still featured an innocent man getting drawn into a spy plot to uncover British military secrets and being forced to go on the run. Hitchcock and his screenwriters, Charles Bennett and Ian Hay, did make numerous additions to the story, including the music hall and London Palladium scenes at the beginning and end, and the tense escape scene on the Forth Bridge. Buchan has no major female characters in his book, but in the film, the spy who starts Hannay on his adventures is a woman, and an entirely new character, Pamela, played by Madeleine Carroll, is a very important part of the action. While the movie title simply refers to the name of the spy organization, in the book there is an actual flight of steps that features prominently in the concluding scenes.