Castle Sinister was a 1932 British horror film produced, written and directed by Widgey R. Newman.
[1][2] The film was apparently set in a lonely mansion in Devon, and was marketed with the tagline "Mad doctor tries to put girl's brain into apeman's head!"
A brief synopsis in the cinema magazine The Bioscope (6 April 1932) offers a plot outline: "The story of a young man's adventures in a large country mansion with a scientist who is engaged in forwarding his theory that rejuvenation by the transfer of certain glands is more than a possibility.
It also mentions "a constantly howling wind and a generous sprinkling of skulls and skeletons".
Castle Sinister is now considered lost with nothing known to survive even in the way of production stills or promotional material.