Castle Sinister is an obscure (and short) British horror film set in a remote Scottish castle starring Mara Russell-Tavernan (me neither). The story involves murder, Nazis spies and ghosts. Well it sounds really promising doesn't it? Unfortunately it falls far short of that promise.
The film meanders, the acting is awkward (probably more painful than the murders) and the budget seems like it was two bob.
It's not all bad, it does have some period charm and the story is quite "Golden Age" in feel. The "Phantom" is cool, and unintentionally funny. The Nazi spy is also sufficiently sinister.