Before filming the scene where Hannay (Robert Donat) and Pamela (Madeleine Carroll) run through the countryside, Sir Alfred Hitchcock handcuffed them together and pretended for several hours to have lost the key in order to put them in the right frame of mind for such a situation.
The 62 imported sheep, upon arriving at the soundstage, immediately went to work on the bracken and bushes that had been brought with them. The infuriated crew had to replace the plants with ones hastily bought from a local nursery.
During a private screening, Sir Alfred Hitchcock asked John Buchan, whose original plot had been used only very loosely, what he thought of the movie so far. Buchan replied: "Fascinating! I wonder how it will end."
In a 1985 interview, Peggy Ashcroft said, "My part took only four days to do. [Sir Alfred Hitchcock was] enormous fun. One laughed a great deal with Hitchcock. I've been told by other people that he wasn't always kind. I found him very kind."
Alfred Hitchcock: (at around 7 mins) The man tossing some litter as Richard and Annabella are about to board a bus outside of the music hall. Walking with him is screenwriter Charles Bennett.
Alfred Hitchcock: [Innocent man wrongly accused] Richard Hannay (Robert Donat) is framed for the murder of Annabelle Smith (Lucie Mannheim).