Note: this article contains SPOILERS. So if you haven't seen the movie and don't want me to ruin it for you, then stop reading.
Now then. I give you Shaun, the unlikeley hero. Dead end job. Lazy as hell. His best friend is a lout , his love life is on the rocks, and to top everything off something's gone terribly wrong in London. Shaun doesn't notice this until a Zombie ("Don't say that word!") shows up in his garden. Essentially, this gives Shaun the kick in the arse he needs to do something with his life. Through the movie, he reconciles with his stepfather, kills one of his flatmates (who's turned into a zombie ("Don't say that word!")), and basically saves his relationship with his girlfriend.
I thought this movie was not only bloody good, but hi-fucking-larious. A few parts of it include extreme gore, so it's definitely not for the squeamish. I'm not squeamish and I found myself cringing a bit at points. The acting is superb, light years beyond any actor in any movie I've seen lately. The screenplay (story) seems excellent, with brilliant, crisp dialogue. On certain levels, it is a satire of "Dawn of the Dead" but on others it's a unique take on the Zombie ("Don't say that word!") genre. A word of note: if you're expecting the usual horror flick here then you should be pleasantly surprised, unless that's what you want in which case this movie might not be for you. I'd give it a shot anyway and see if you don't come away with something from having seen it.
P.S. You'll understand the whole "Don't say that word!" joke if you've seen the movie.
