The film takes some of the visual gestures that animate the book (sheep diseases, religious mania etc), but then scoops out all the surrounding connective tissue, everything that makes the book make sense, replacing it with some kind of pulp which looks to me as if the writer was shaken violently awake in the middle of the night and asked to regurgitate the story lines from the last five horror movies he had seen, except his notes got all scrambled up - the result being a sort of plot-pudding, full of screaming and running about and unexplained (unexplainable) twists.
No disrespect to anyone, and I know what sort of pressures the screenwriter was under, but the film does not, in any sense, 'adapt' Sheep, the novel. Sheep is a careful, thoughtful book, with a meticulously worked plot. It is also (I am informed) scary (one reviewer said it was the only thing he had ever read which did actually scare him), which the film of course, despite its most strenuous efforts, fails completely to be. The book is not about some vague Disneyfied version of Welsh mythology (nice and safe and distant in these troubled times), it is about Christianity, the Bible: about what happens when religion turns to madness. The scariness is in the waiting, the hinting, the accumulation of detail, drip by drip. It is about fearing, dreading, while something unfolds which cannot be understood until it is too late. I may not have succeeded in any of this, but I was trying. The film just flaps about from one random thing to another, papering over the cracks with tiresome 'shock' effects and Maria Bello screaming.
Copies of Sheep are hard to track down now without paying a lot of money, but I would love it if the people who were disappointed in the film were to read the book. Please don't judge the book (or any of my other books) because you didn't like The Dark: there is almost nothing connecting the two things. Give the book a try: you'll be surprised.
Thanks for your time.