Laird of the Castle, Max, brings his bride home to the family pile unaware (or not) that secrets lurk within.
Well, this is a mess - I suspect some of these cast names are merely the Anglicized versions of some of the actors doubling up.
Indeed, the names listed in the opening credits (Patrik Walton, Carole Windsor, Rex Vidor, James Borden, Peter Hardy, Bredon Brett and Robert Mayor) all appear to be spurious Anglizations, the exact connection of which to specific actors is unknown. Curti's Italian Gothic Horror Films, 1957-1969 credits the doctor as Luigi Severini, an actor who does not appear to exist, and appears to be a confusion for Leonardo Severini. Some sources credit him as the doctor, but I am confident it is Dell'Arti portraying him.
Visually stylish, though poorly scripted, with an excellent score by Riz Ortolani. This film was perhaps the first truly gory Italian horror film, and was influential in ways out of proportion to its origins (filmed in a mere three weeks after Castle of Blood to use that film's sets and crew).