This one is a very qualified recommendation. This is a 7 episode Netflix mini-series - the big problem is that it should have been 3 episodes.
Minor spoilers to follow;
So the first episode is PAINFULLY slow. It just establishes the setting and some of the characters. At the end there's a hint that something supernatural (or anything slightly interesting) is going on.
2nd episode is also painfully slow. Same deal, slightly larger hint at the end.
3rd episode is where it starts to get good - maybe fast forward through the first 2. They still manage to slow things way down with filler even after the story properly starts in some scenes though.
So as for the premise (this is where the spoilers start) - so you know how in "The Walking Dead" they call the zombies "walkers" and seem to have had no zombie-based fiction prior to the series? Just doesn't exist in their world so they have no point of reference, no idea what a zombie is, etc.
In Midnight Mass it's the same thing, but there's no vampire lore. No one has ever heard of a vampire, has no idea what one is... and if you happen to also be Catholic, where there's already a tradition of drinking the "blood of the savior" - which the church insists is a genuine miracle each and every time - well you could see how they might get confused. The situation then spirals out of control from there.
Anyway, if you get past the slow parts (more than half, unfortunately) the rest is entertaining.
*corrected it from "Black Mass" - that was a Johnny Depp mob movie I think? This one is "Midnight Mass".
