I have often thought about dragonriders of pern as a movie. I am not sure thread really would show well. The books really emphasize people’s fear of thread. But I don’t see anything visual about it that would really inspire that fear on the screen. Even while reading, I often felt the fear level was unrealistic. And a lot of peoples motivations were based on that fear. Now a great writer might be able to adjust things to work aroundvthat, but it seems tough.