I'm always on the lookout for any anthologies. Books TV movies it doesn't matter. I love a great short story. I've recently been going through the "Thriller" TV series and it's been hit or miss. But the presence of host Boris Karloff led me to "Black Sabbath" which I'd heard of before but never realized was an anthology. "Black Sabbath" consists of three stories strung together loosely by Karloff's introductions.
It all kicks off with a tale called "Drop of Water" which is a very creepy little ghost story. If I had seen this thing when I was younger it probably would have caused many sleepless nights. It's loaded with creepy sounds incredible atmosphere and some great looking sets. Then...wham! It hits you with some damn scary moments. It's not gory or anything but it's loaded with overwhelming dread. I honestly didn't think any of these older films could scare me anymore but this story certainly did.
The next story called "The Telephone" is also quite good but it suffers from a simple rushed ending that I almost missed. "The Wurdulak" tries to be the showcase piece of the film but I think it falls flat. It's moody and eerie enough but Boris Karloff plays the lead role and frankly isn't convincing. This one concludes in the most logical fashion and it drags quite a bit.
I can't recall watching any Mario Bava directed films in the past but given the strength of "Black Sabbath" I'll probably watch more of his filmography. The acting other than Karloff's disappointing role was very well done. And there are some very beautiful women featured throughout. Michele Mercier, Suzy Andersen, and Rika Dialina are all stunning.
This is definitely worth watching mostly for the terrifying "Drop of Water"

Boris Karloff introduces this triptych of short stories. I found the first, the shortest, to be the least interesting centring around a greedy nurse who robs a corpse of a valuable ring only to find that it's erstwhile owner isn't quite finished with it, or her, quite yet! The second sees a beautiful woman return to her apartment one evening only to find herself subjected to repeated telephone calls warning her that she shall not see the morning! Michèle Mercier is quite effective as the terrified "Rosy" in this story. Finally, Karloff himself takes to the stage in a rather lengthier, enjoyable, vampire story that sees a travelling count discover the body of a dreaded bandit and take it to a nearby farm. It's only once there, and with the return of the father "Gorca", that he begins to realise that this danger has already been "invited in"! The productions have a very Hammer look to them, the make up and visual effects (especially in the first story) don't hold up so well, but in the main, the three stories are quite solid with portentous messages of revenge for those who would steal or cheat or kill! You are unlikely to recall it a few days after watching, but Bava knew how to do budget/studio horror quite well and the last two stories make a decent fist of developing some sense of menace and threat. Good fun.