This is one of the best horror films I've ever seen, and I will safely place it in my all-time horror-film Top 10. It's the scariest movie I've experienced in a theater since James Cameron's Aliens 20 years ago. The Descent takes everything I dread in this world (caves, the dark, bat-like human creatures that want to eat me) and throws them in my face. If you are a horror fan, and you think the genre has run out of ways to freak you out, see this movie now.
Six female friends go on their annual adventure trek, and their unofficial leader, Juno (Natalie Jackson Mendoza), has made the decision that this trip will involve cave-diving. The women head into the Appalachian mountains, find themselves a hole and jump on in.
The movie is scary enough as the women get in over their heads and find themselves trapped and lost. Director Neil Marshall plays many disorienting tricks with the dark and claustrophobia, making the movie effectively uncomfortable and foreboding. As the women go deeper into the cave, they start to hear strange noises. Then, 45 minutes into the movie, the monsters show up.
Marshall didn't have a big budget for this film, and that's a blessing. The creatures and the bloody carnage they create are old-school. The monsters, slimy grey bat-like creatures that make awful noises and like fresh meat, reminded me of Gollum from The Lord of the Rings, the major difference being that there's absolutely nothing funny about them.
In addition to the generally disgusting noises the monsters make (an assortment of clicks and screeches), a sort of "evil glee" serves to freak the viewer out. When the monsters feast on a fresh kill, they laugh and hop about in a manner that is sickening. Wonderfully, horribly sickening.
When the movie was over, I had a slight case of the creeps walking down the theater tunnel leading to the exit. (It felt cave-like, and I thought a cave crawler might come and get me.) Then I got a little creeped out when I walked outside to my car. (It was really dark.) When I got home, I ran around the apartment turning on lights, only to be freaked out again when I opted to take a shower. (The sound my shower makes when turned on sounds like the screech let out by the cave mutants in the movie.) I don't scare easily, but this damn movie put me in a state of unease for many hours after.
For the U.S. release (the film has already enjoyed cult success in its native England), the ending has been changed--actually, not so much changed as shortened. I have seen the original British ending (with about another minute of footage that can be found on the Internet), and it's better. The ending for the American release isn't bad, but the final shot in the original version ties the film together in a more meaningful fashion.
With The Descent, Marshall has raised the bar for unrelenting, ultra-disturbing horror. Let me say this: I'm hoping no directors in the near future manage to raise that bar any higher. I don't think I could handle it.