The longer we spend working in the horror realm, the more apparent the occurence of the horror auteur becomes. Some of them are masters working from start to finish to create a wonderfully scary horror film. Others plainly couldn't get anyone else to film the terrible script they had written. Whatever the case, all of them show a singular devotion to the entire process of telling a horror story on film.
Perhaps more than any other film genre, the creation of a horror movie is often done with as few personnel as possible leading to a necessity to keep those few familiar with the story involved as long as possible. If you wrote the script, you must have an idea of what should be filmed; you get to direct. Many a B-grade horror film comes about exactly that way. Some of them like Leprechaun start franchises that are usually taken from the original creator and toyed with until we're sick of them. Others like Halloween become classics in spite of the sequels. Then there is the rarest of all.
Auteurs like Sam Raimi and George Romero have created fantastic series and stuck with them. Bringing us entry after entry of the same thing that made their first creation unique. But series like Romero's Living Dead and Raimi's Evil Dead are the exception. For the most part, horror is made by horror fans and once that great idea hits the screen, it doesn't matter how much love and attention the writer/director gave it, it's lost in the translation.
To qualify for this index, the individual has to be credited as both a writer and director for a horror movie we've reviewed. Only the movies that fulfill this qualification are listed for a given writer/director.