28 days later, Jim (Cillian Murphy), a young bicycle deliveryman, wakes up in bed in a London hospital that is mysteriously abandoned. Confused and scared, Jim wanders equally empty streets, then finds a church filled with bodies unfortunately for Jim, one of these is not dead and he discovers what the infected are like snarling, fury-driven, red-eyed and incredibly fast-moving things that simply want to shred everything from limb to limb. Jim is rescued and eventually becomes part of a small band (Naomie Harris, Brendan Gleeson, Megan Burns) traveling in the direction of a taped radio broadcast that promises military-provided safety and an answer to infection.

The tone and content take an unusual turn when the travelers reach their destination, going hardcore horror again for the finale. Conceptually, director Danny Boyle and writer Alex Garland (who previously teamed on THE BEACH) have fully thought out the implications of their universe, everything from subtly noting how different views of the world will alter behavior to the dramatically valid concept that rage is hardly the sole province of mutants. The characters are shaped in quick but telling strokes we come to like Jim and his comrades very much in a short span of time and Boyle and company have done a brilliant job of making London appear to be totally empty, a nightmare-scape of debris, corpses and futility.

The filmmakers dont skimp on the scares, either. Theres a scene in a tunnel thats is an exercise is pure fear of the dark, and the movie is good at shifting expectations, with infection sometimes coming from hide-in-plain-sight sources. Gore is moderate -- this is to say, its hard-R territory, but no one is going to confuse 28 DAYS LATER with DAWN OF THE DEAD in terms of splatter. The digital photography maintains an atmospheric, filmic look under the gray skies and at night, with one shot of a car passing flowering fields looking like a startling Monet painting in motion.

The cast is excellent, with Murphy an appealing focal point as an unprepossessing fellow who develops great strength without becoming unrecognizable, Harris as a self-protective sort whos not as tough as shed like to be, Noah Huntley as a compassionate pragmatist and Burns as a very natural 14-year-old. The two A-list U.K. actors aboard, Gleeson as a loving father and Christopher Eccleston as an Army officer with some peculiar concerns, both treat the material perfectly seriously, playing their roles as fluidly and reflectively as they would in a straight contemporary drama.

The result of the realistic performances, well-modulated writing and overall non-hysterical tone gives 28 DAYS LATER added emotional and philosophical dimensions, while simultaneously making it even more terrifying. At the end of the movie, the feeling is of having gone through something of substance and duration -- this is a horror movie that sticks with you on all levels.