Here's a movie often incorrectly billed as a zombie movie, they're infected humans, damnit! What makes 28 Days Later so amazing is the low budget and focus on character. Low budgets often limit directors, but Danny Boyle makes the best out of it, creating an incredibly realistic world without CGI or focus on lots of gore. The film is grainy, the music is ominous and dark all adding to the mood that crawls under your skin. The very concept of movie works on so many levels, while never explicitly explained, we find Jim awakened after some sort of brain/head surgery. Imagine waking up from surgery to find yourself alone, the entire city abandoned, not knowing what went on, and then to find insane and vicious people hunting you down. Terrfying, no?
The movie uses typical elements of the zombie genre, involving man versus man conflicts where the human's lack of cooperation doom them and the concept that high tech weaponry is useless in the end. However, 28 Days Later succeeds by being very focused as a result of it's budget, centering on the characters, not the infected. It's unusual perspective on the horror (we know the infected are coming before the characters do, the tension is now that we fear for the characters unknowing.) is fascinating and the movie just works on so many levels. It's incredibly well made and brings class to a genre not respected by many people.