I'd like to add a few non-mathematical comments to the review from Jon Salt above. First, I think it should be pointed out that the film is very violent and gory. (I was not expecting this from the descriptions I had heard before I rented it for my wife and myself to watch one quiet evening.) Secondly, I see the movie as presenting a rather subtle metaphor. I cannot be sure that this is what the authors intended, but I certainly prefer to think of "the cube" not as literally being a giant mechanical death-trap but as being representative of the dangers and obstacles created by our society itself. As we learn in the film (bit of a spoiler coming up...don't read it if you don't want to know!), the cube was built by people who each made a little part of it without really thinking or caring about what they were doing...just "their jobs". My wife was then bothered by the fact that the people who actually put the parts together must have seen what they were making, and this made her have trouble "believing" the film. But, if you view it my way, you realize that the deadly traps in the cube (created by ambivalent, not evil people) are not all that different than the "traps" we encounter in the real world. Cigarettes, welfare that pays more than minimum wage but not enough to live in a decent place, heavily marketed automobiles and alcohol that together become a recipe for danger...these are all deadly traps that we face every day and they really were created somewhat unintentionally without anyone being able to really see the whole thing at once. (Sorry if I'm getting too preachy here!)

For fun, check out the film's weird Web site at cubethemovie.com.