If this movie is no longer free on YouTube, you can find where it is streaming at JustWatch.com: https://www.justwatch.com/us/movie/the-satanic-rites-of-dracula
CHRISTIAN DISCLAIMER:
Although this is a movie about satanic rites and a satanic cult, it is Christian and Catholic friendly. The cult is seen as evil and the traditional Dracula rules of crosses and crucifixes are powerful enough to ward off satan, vampires and evil.
WHAT CAN AUTHORS LEARN FROM THIS MOVIE?
This is a modern Dracula story (it was modern in 1973 😊) and this is a good example of how to mix a modern contemporary vampire story with the old-world rules and images of the old gothic vampire genre.
A writer can also learn about adding obstacles to build tension and conflict. The obstacles used in the movie are easy enough to envision them in whatever you may be working on.
This is also an easy enough "saving the world from evil" storyline that is not complicated or convoluted. This movie would be easy enough to reverse engineer and learn how to create a story spine for a force that could destroy the world.
There is a moral tale and it's the basic good vs. evil.
Here is the review I did on YouTube, if you are interested in viewing it.