High Treason is a 1929 film based on a play by Noel Pemberton Billing. It was directed by Maurice Elvey, and stars James Carew, Humberstone Wright, Benita Hume, Henry Vibart, Hayford Hobbs, Irene Rooke, and Jameson Thomas. Raymond Massey makes his first screen appearance in a small role. The film was initially produced as a silent but mid-way during production, Elvey was pushed by the studio to add sound to the film in order to cash in on the talkies. Although a third of the film was filmed in sound, Elvey maintained much of the silent footage and dubbed over the dialogue for shots that were originally silent, with Elvey himself voicing some of the minor characters, which he admitted when interviewed by the Manitoba Free Press shortly after the film was released in the US. Likewise, BIP's Blackmail, directed by Alfred Hitchcock, was also turned into a sound picture mid-way during production (concurrently when High Treason was also in production) and many of the silent scenes used dubbed dialogue and sound effects in a similar fashion to High Treason.

The sound version of the film was presented in a London trade show on 9 August 1929, then went into UK general release in silent and sound versions on 9 September 1929. The sound version was released in the US by Tiffany Productions in a heavily cut version (running just over 60 minutes) on 13 March 1930. The silent version and a trailer for the sound version are preserved and held by the British Film Institute; the only known surviving original copy of the sound version is a lavender fine grain of the American release version held in the collection of Alaska Moving Image Preservation Association (AMIPA), which has been recently restored by the Library of Congress.

The film is a science fiction drama set in a futuristic 1940 (though this was originally set in 1950 for the silent version). The plot and aesthetics of the film are heavily influenced by Fritz Lang's Metropolis.