GRRM SF Horror
One of the best written and scariest things he's written was a novelette called Sandkings, originally published in Omni magazine. It won Hugo, Nebula and Locus awards at the time.
It was adapted into a one hour, single episode "for TV" show but that was done on the cheap and severely cut down.
It would be an excellent candidate for expansion into a movie, albeit with some small script adjustment for the unending bleakness, lack of any likeable characters and "everybody dies" ending.
Biting the hand that feeds IT
