Although it's part of the blaxplotation genre, I can't see much about Scream Blacula Scream that's exploitive. It's just about what happens when a bunch of black people meet a vampire who is also black. The original Blacula was a disappointment. Despite a strong lead from William Marshall in the title roll, the film's low budget got in the way of the story and the movie was just plain boring. The sequel is a lot more fun.
The movie opens as a voodoo ceremony brings back the vampire to un-life, and he thanks the man who did it (Richard Lawson) by promptly vampirizing him. While out one evening, Blacula arrives at the house of Lisa (Pam Grier) who is dating former policeman turned novelist Justin (Don Mitchell). Taking his real identity as Prince Mamuwalde, the vampire lays on the charm and becomes attracted to Lisa, who is taken over as the head of the voodoo sect after the death of mother. At the same time, people around town begin to die in a strange way- all the blood is drained from their bodies and there are two marks on the neck. The detective assigned to the case thinks the bites were caused by a snake, but Justin isn't too sure…
In many ways, Scream Blacula Scream is like a black American version of Dracula A.D. 1972 though nowhere as fun because it's not as ridiculous. Unlike Peter Cushing in that film, Justin begins to realize what's going rather quickly (despite the fact he doesn't have a Ph.D. in Occult Sciences) and his methods of suspicions are rather plausible.
Watching this film, particularly towards the end, I was little disappointed that it was content to be nothing more than a low budget horror film, as Marshall is such a good actor that he gives Blacula some interesting depth and surprisingly noble intentions, and his chemistry with Grier is so strong I regretted this wasn't more of a love story.
However, Scream Blacula Scream wants to be fun, and succeeds in that goal. It is not an Academy Award winning classic, but, like Dracula A.D. 1972 is both intentionally and unintentionally good, making it a good choice for a fun evening with a pizza and cheap beer (although I would recommend some high caffeine tea as more reasonable excursion).