The 39 Steps is a 1935 British spy thriller film directed by Alfred Hitchcock, starring Robert Donat and Madeleine Carroll.

[3] It concerns a Canadian civilian in London, Richard Hannay, who becomes caught up in preventing an organisation of spies called "The 39 Steps" from stealing British military secrets.

Mistakenly accused of the murder of a counter-espionage agent, Hannay goes on the run to Scotland and becomes tangled up with an attractive woman, Pamela, while hoping to stop the spy ring and clear his name.

"[4] At a London music hall theatre, Richard Hannay is watching "Mr. Memory" demonstrate his powers of fact recall by answering trivia questions from the audience, when gunshots are heard.

She claims that she has uncovered a plot to steal vital British military information, masterminded by a man missing the top joint of one finger.

Hannay finds a map of the Scottish Highlands clutched in her hand, showing the area around Killin, with a building named "Alt-na-Shellach" circled.

Early the next morning, Margaret sees the headlights of a police car approaching and wakes Hannay; before he flees, she gives him her husband's coat.

When Mr. Memory is introduced and begins taking questions from the audience, Hannay recognises his theme music — a catchy tune he has been unable to forget.

The script was originally written by Charles Bennett, who prepared the initial treatment in close collaboration with Hitchcock; Ian Hay then wrote some dialogue.

The production company, Gaumont-British, was eager to establish its films in international markets and especially in the United States, and The 39 Steps was conceived as a prime vehicle towards this end.

[3] The 39 Steps is one in a line of Hitchcock films based upon an innocent man being forced to go on the run, including The Lodger (1927), Saboteur (1942) and North by Northwest (1959).

The film contains a common Hitchcockian trope of a MacGuffin (a plot device which is vital to the story, but irrelevant to the audience); in this case, the designs for a secret silent aeroplane engine.

At around seven minutes into the film, both Hitchcock and the screenwriter Charles Bennett can be seen walking past a bus that Robert Donat and Lucie Mannheim board outside the music hall.

As author Mark Glancy points out in his 2003 study of the film, this was familiar ground to Hitchcock, who lived in Leytonstone and then in Stepney (in the East End) as a youth.

This jarringly unusual development—the main character is apparently killed while the story is still unfolding—anticipates Hitchcock's Psycho (1960), and the murder of Marion Crane in the Bates Motel.

Andre Sennwald of The New York Times wrote: "If the work has any single rival as the most original, literate and entertaining melodrama of 1935, then it must be The Man Who Knew Too Much, which is also out of Mr. Hitchcock's workshop.

A master of shock and suspense, of cold horror and slyly incongruous wit, he uses the camera the way a painter uses his brush, stylizing his story and giving it values which the scenarists could hardly have suspected.

"[11] John Mosher of The New Yorker wrote "Speed, suspense, and surprises, all combine to make The 39 Steps one of those agreeable thrillers that can beguile the idle hour...Mystery experts will enjoy the whole thing, I think.

Ethan Brehm of HiConsumption observed that Hitchcock "takes influence from Russian silents and German expressionism from the decade prior, but makes each frame his own canvas and has some early fun with POV here in the process.

The website's critical consensus reads: "Packed with twists and turns, this essential early Alfred Hitchcock feature hints at the dazzling heights he'd reach later in his career.

[3] In chapter 10 of J. D. Salinger's novel The Catcher in the Rye, the protagonist Holden Caulfield recounts the admiration that he and his younger sister Phoebe have for the film.

It was written in 1995 by Simon Corble and Nobby Dimon, a version rewritten in 2005 by Patrick Barlow has played in the West End and on Broadway.