Castle Sinister, released in 1932, was a 50 minute (4410 foot long) black and white British horror film produced by Delta Pictures that’s now classified as ‘lost media’. The film is so obscure that there is no remaining footage, stills, teasers, or posters and most of the actors don’t have any photos available online. It’s unfortunately common for early films to vanish, especially those made in the silent film era before 1929 and early talking pictures from the 1930s.
Source: ‘Castle Sinister’: The Terrible 1932 British Horror Film Lost in Time – Curious Archive