Donald Cammell's sort-of-slasher is something of a mess, beginning as a study of some tediously uninteresting characters in a desert community occasionally interrupted with more-giallo-than slasher murder sequences before without warning heading into much more conventional horror/thriller territory towards the end. It feels like neither one thing nor another and I had a distinct feeling of studio interference ... but it seems to have been the only film that Cammell made that wasn't heavily interfered with. I was fairly bored by it and a bit irritated.
The Arrow BD does have one major compensation though and that's the excellent BBC documentary Donald Cammell: The Ultimate Performance which is presented as an extra. It's well worth a look and features pretty much everyone from Jagger, Fox and Roeg to Kenneth Anger and Barbara Steele.