This is my favorite module from TSR's Golden Age (though it might considered Silver Age by some). I just love it; warts and all. Yeah there are some real leaps in logic in this one and there are plenty of reasons NOT to like it, but I don't care. I think it is great. It's a Hammer Horror film in D&D form right down to the small "Hammer Hamlet" village with terrified peasants. There are vampires, gypsies, werewolves, really strong zombies, gargoyles. Even a huge pipe organ played by the vampire. You can almost hear Toccata and Fugue in D minor while running it. I have played through this once and I have ran it three or four times. I would love to try it sometime under the Ghosts of Albion rules. I took my D&D 5e group through it when they completed Castle Amber to make for a "Mists" series. It was fantastic.
Get this and admire those wonderful maps.
[5 of 5 Stars!]