Yes, you read correctly. This is, to my knowledge, the only Islamic Horror movie. Now, Muslim nations such as Pakistan, Turkey, etc. have produced plenty of horror movies. But this is the only one that presents the genre of horror from truly Islamic mindset. All the others were copies of Western / Christian based horror.
In a nutshell, a concert flautist and his astronomer girlfriend go to rural Turkey to investigate a solar disturbance that threatens the earth. While there, the flautist is taken under the wing by a Sufi (Islamic mystic) who helps prepare him to battle a powerful djinn (demonic spirit) - and they do battle using nothing but music as their weapons.
The film has a few flaws, and the symbolism will be a bit confusing to some who are unfamiliar with the base material. But all is all, its a good film; and if nothing else, it holds its own as a unique piece of cinema.