In 28 Days Later, animal-rights activists free some chimps that have been infected with a deadly virus. The virus is a psychological item that infects within seconds and puts its victims into a permanent state of murderous rage. Victims make furious sounds and also tend to spew blood and look like zombies, so it's a gross and noisy sort of situation.
Then, 28 days later, a young man wakes up in hospital where he has been lying in a coma. He walks outside to discover that his city -- London, England -- appears deserted. He knows nothing of the apocalyptic events unleashed by the virus and he wanders around the apparently empty streets. Our hero, Jim, is a bike courier (Cillian Murphy) who will soon encounter a few survivors and a lot of "infected" ghouls.
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