The end of the world as we know it will only be the beginning of something a good deal worse. That's been the premise of a great many movies, from The Road Warrior to The Day After to George Romero's Living Dead trilogy. 28 Days Later is like a distillation of what made all three of these things frightening: the survivalism, the nihilism, and, yes, the flesh-eating zombies. In fact, it's almost misleading to bill this as a "zombie horror" movie (printed on the blood-red one sheets for the film). It starts as a nifty horror shocker, but quickly mutates into a smarter and more absorbing movie -- a story of ordinary people caught in terrible circumstances. Action and gore fans are not liable to be disappointed, but the movie has much smarter blood in its veins than, say, Jason vs. Freddy.
SF and horror lend themselves very naturally to satire and social commentary. Most of the time horror movies paint an unsparing picture of humanity -- that man is his own worst enemy, namely, and that we have more to fear from the guy next door than from some nameless toxic spawn from outer space. 28 Days Later compacts that even further: here, the toxic spawn IS the guy next door, and you could become one yourself in a matter of seconds. It serves as a metaphor for how social decay is contagious, about how a quiet suburban block can be transformed into a burned-out crater by its own inhabitants if you raise their ire enough.
