Castle Sinister is a 1948 British mystery film directed by Oscar Burn and starring Mara Russell-Tavernan.
[2] It was remade in 1954 with the title The Devil's Jest, again starring Mara Russell-Tavernan.
Both are attributed to the castle's mysterious phantom but actually are the work of an enemy agent.
[3] Castle Sinister reflects the immediate post-war British concerns of the threat posed by Nazism (rather than Communism), and the possible existence of secret Nazi organizations in Britain working to rebuild Germany.
[4] It is one of few films of the period to examine the operations of enemy intelligence agents, saboteurs or traitors.