"'The Thirty-Nine Steps,' said Francis"

The Thirty-Nine Steps is a 1915 novel by John Buchan (1875-1940), an adventure in which the protagonist, Richard Hannay, finds himself on the run from the both the British police and German spies when he stumbles into a plot to destabilise pre-war Europe. It has been adapted for film and television a number of times, the most notable being Alfred Hitchcock's 1935 film, starring Robert Donat and Madeleine Carroll.