"The Castle of Otranto" was a novel by Horace Walpole which was published in Britain in 1764. This is Jan Svankmajer's version of the story--told in an odd fashion as those familiar with the Czech filmmaker would expect.
The story starts with a documentary style piece where a professor claims to have found the actual Otranto castle not in Italy but in Czechoslovakia. This is all fake...though it looks real. And, periodically, the film cuts back to this 'expert' as he talks about his supposed research. The rest consists of a retelling of the novel and it actually sticks pretty close to it...and it's told in a style very similar to Terry Gilliam's animations from "Monty Python's Flying Circus"...with cut outs moving about through the use of stop-motion. Unlike Gilliam's animations, however, this isn't funny...though occasionally it's pretty bloody.
All in all, one of Svankmajer's least enjoyable films. It lacks the goofy creepiness I love and folks looking for this might be disappointed by a story that is amazingly normal compared to Svankmajer's other films.