Claustrophobia can be a very effective tool for creating good horror. Ridley Scott's Alien and John Carpenter's The Thing both made great use of a confined environment, but if you thought being trapped in a tiny Antarctic outpost while your partners were being gradually assimilated by an alien life form was bad, that's going to seem a picnic compared to what you'll be in for with The Descent. Right here is a movie that takes claustrophobia to its logical horrifying extreme, and uses it to full effect.
Speaking of The Thing, part of what made that movie interesting was the choice to use an all-male cast, subverting a few horror clichés by taking them out entirely. It is not too hard to find movies that have an all-male cast. A lot of my all-time favorite movies have exactly that, but what about the other logical extreme? Finding movies with an all-female cast is something of a rarity, and even more rare is finding an all-female cast in a genre that isn't stereotypically feminine to begin with (i.e. melodrama). The Descent is one of those rarities. It has a grand total of one male character of significance who doesn't make it through the first ten minutes.
Sarah (Shauna MacDonald) is something of an adventurer. She and her friends like to embark on all kinds of exciting thrill-seeking experiences. It all goes great until a tragic accident happens ironically after one such adventure has ended. While driving to her hotel, there is an accident on the road. Sarah's husband and daughter are both killed, and she herself is severely traumatized.
A year later, Sarah's friends get back together, along with a reckless skydiver named Holly (Nora-Jane Noone), and try to distract her by inviting her on a cave-diving expedition. Everything goes fine at first until it turns out that her friend Juno (Natalie Mendoza) had slightly more complicated plans than a simple cave exploration trip. They eventually find themselves trapped, claustrophobia sets in, the girls become panicked and tension mounts between them as they search for a way out.. and that's not even getting into what starts happening about halfway in.
This is a film that will leave you uncomfortable even before anything actually terrifying happens. If you have ever been in a cave, you will probably know how claustrophobic and environment it can be. We get a number of scenes involving the characters moving through spaces that are just large enough for them to crawl through, but also long enough that one can't help but fear what might happen if it gets to narrow.
There is also the anxiety that comes from not knowing for sure the way out, and the disorientation that comes from the fact that much of the movie happens in the dark. For most of the film, it becomes hard to see what is going on. Everything that can be seen is shown through whatever light the women are able to produce and occasionally the infrared setting on their video camera. This in turn helps to create the feeling of being trapped in a cave, with limited resources.
As far as character development goes, this movie is not the strongest, though that is not to say it is handled poorly. You do get connected to the characters and subsequently want to see them get out in one piece, but it is easy to lose track of who is who, especially once they enter the caves. However, this does help to add a layer to the disorienting atmosphere. Once they are in the caves and the lighting is limited to whatever the main characters can produce, it becomes harder to tell who is where, who is in front and who is behind. In that sense, the fact that it becomes hard to tell people apart actually works to the film's advantage.
Modern horror films have a tendency to fall into various traps. Often times they will have some really good idea that ends up being turned into a generic slasher film, or it will be an idea that was just silly to begin with. It is rare to see a well-executed horror film, but The Descent is definitely one of those exceptions. It is a compelling but never comforting piece that will make any claustrophobic cringe in their seat.