The world has changed over the past 28 days while Jim (Cillian Murphy) was in a coma. After being a victim of a bicycle accident he doesn't know what has happened. After waking from his coma Jim finds London to be lifeless. With destruction at every turn Jim soon finds that what he though was deserted was in fact inhabited with homicidal zombies. A blood borne disease released from a British lab is to blame. The disease is rapidly transmitted from test monkies to the whole population and Jim must find a way to survive. Jim discovers a group of survivors and they all head to Manchester; where they heard there'll be an army of protection, but when they arrive their troubles have just begun.