Robert Powell was cast in part because of his success in the mini series Jesus of Nazareth. The script did add a romantic interest for Hannay, played by Karen Dotrice. "You can't make a movie without women", said Smith. "You can't go through life without women." [1] The production was shot using 35mm film rather than high-definition cameras. Hawes told Matthew Bell of Broadcast that:

In the book, the 39 steps lead down to a beach and filmically there is not much you can do with that. Today, audiences demand more of a grandstand finish. That was the major liberty we took – the ending. People can say, 'You're not being true to the ending,' as they stay away by the millions... [Big Ben was chosen for the end] because it was an analogy we were working for – Europe was a time bomb in 1914. And we figured that the centre of European politics would undoubtedly have been the House of Commons. So we thought, 'Why not finish the film in the political seat of Britain?' [1]

Alfred Hitchcock's 'The 39 steps'

Powell said "If we had tried to use Buchan's book literally we would not have had a film at all. For one thing it's thoroughly anti-Semitic and no one would get away with that." [3] Kirby, Walter (2 March 1952). "Better Radio Programs for the Week". The Decatur Daily Review. The Decatur Daily Review. p.42 . Retrieved 28 May 2015– via Newspapers.com. Producer Greg Smith said he wanted to make the film because he had always been a fan of John Buchan's books and wanted to do a version of The Thirty-Nine Steps which was "true to the period in which the novel was set, just prior to the Great War, when Europe was one huge powderkeg and nobody knew what a world war was." [1] Filming took place on location in Scotland. [2] Locations used included the area around West Register Street in Edinburgh for the London scenes at the start of the film, Bo'ness railway station, [9] Kelvingrove Art Gallery and Museum for the interior scenes of St Pancras railway station, [10] Glasgow City Chambers, Culross, Stirling Castle, [11] Dumbarton Castle, [12] the highlands of Argyll and Loch Katrine, used for the finale. [7] [13] Filming [ edit ] Harper, Sue (2011). British Film Culture in the 1970s: The Boundaries of Pleasure: The Boundaries of Pleasure. Edinburgh University Press. p.273. ISBN 9780748654260.

a b c d e f g h i Judy Klemesrud (27 April 1980). "A New Film Version of 'The 39 Steps': Opening This Week". New York Times. p.D8. Together by the loch, Hannay and Victoria kiss before she is hit by a bullet fired by a surviving gunman, falls into the loch and disappears. The story concludes four months later, after the start of World War I, when Hannay, in an army officer's uniform, is waiting to meet someone at St Pancras railway station. Harry appears, saying that Victoria wanted to say goodbye, and Hannay sees her in the distance. Harry tells him, "top secret, old man." Victoria disappears behind a luggage trolley and Harry tells Hannay that she will see him after the war. As he tries to escape the apartment building unseen by the assassins while in disguise, a friendly milkman passes by Scudder, recognises him, and greets him loudly, which alerts the assassins. Greg Smith said that John Buchan's son, Lord Tweedsmuir, was pleased the film used more of his father's book, and that he thought his father would have liked the Big Ben ending. [1]Not His Sled: Unlike in the novel, the mysterious phrase "the 39 steps" refers to a staircase in St Stephen's Tower, leading to where the assassins have placed their bomb. Filming was originally scheduled for 1958 but was postponed in January that year due to a drop in cinema attendances. [6]

Rimington, Stella (11 January 2011). "John Buchan and The Thirty-Nine Steps". The Telegraph . Retrieved 12 August 2023.Tony Williams Interviewed by Andrew Spicer, London, 18 March 2011, Michael Klinger Papers accessed 16 April 2014

The film's period setting gives it quite a different flavour to other spy films, including the previous film versions of this story. The re are splendid old cars, steam trains and an early monoplane. The period trappings are not completely authentic, and the railway train is a 1950s one with "Midland" painted on the carriages to represent the more period appropriate Midland Railway. But the film has good production values, with a generally convincing sense of period and it benefits from a pleasing score by Ed Welch . Laws, Roz (2 January 2009). "Christmas TV on the BBC was a treat but New Year's Eve was awful". Sunday Mercury . Retrieved 4 January 2009.

There are also some major new elements, not featured in either of the two previous films or in the book. David Warner's character disguises himself as establishment worthy Sir Walter Bullivant (George Baker) in two high level meetings and no one notices - thanks to the simple use of a false beard and glasses. This is a particularly improbable idea that should have been dropped. In Ralph Thomas's remake, Kenneth More is thrown into the mystery by the death of a beautiful spy who has told him of an enemy group, The 39 Steps, which has stolen plans for a British missile. The Thirty Nine Steps[ sic] is a British 1978 thriller film directed by Don Sharp, with screenplay by British playwright Michael Robson, based on the novel The Thirty-Nine Steps by John Buchan. It was the third film version of the 1915 novel. Colonel Scudder (John Mills) is a British spy who has uncovered a plot to assassinate the Greek premier on his visit to London, something that will spark a crisis in the Balkans and likely lead to war in Europe. When he finds himself pursued by enemy agents determined to kill him and take possession of his evidence against them, Scudder seeks sanctuary in the apartment of a neighbour in his building, Richard Hannay (Robert Powell). Film is absolutely right for this project. It has scale, big exterior locations and that's something that still challenges HD.... The HD cameras available to us on our budget are still vulnerable in difficult weather conditions [encountered during filming]. There's no doubt that what we've got on 35mm is just so much more detailed. It has so much more depth of field and richness than we could have got on HD. [7] Historical inaccuracies [ edit ] Hannay (Penry-Jones) being chased by a 1916 biplane in a promotional image from the production. Penry-Jones was "delighted" that the scene was included, but it drew criticism and viewer complaints for its historical inaccuracy.