This article details the various background character deaths that occur in 28 Days Later.
- In the opening scene, an animal rights group break into a medical research lab to free a number of chimpanzees that are being experimented on. What they do not know is that the chimps in question are infected with a devastating "rage virus" that causes its hosts to become locked in a state of homicidal fury. The activists release a chimp from its cage only for it to infect one activist by biting her, who succumbs in seconds and spits blood in her friend's eyes, spreading the virus. This is the beginning of a deadly epidemic that all but wipes out the population of Great Britain.
- A month following the outbreak, Jim wakes up in hospital having spent 28 days in a coma following a traffic accident. He finds the hospital is completely empty and exits to find that the whole of London is deserted and devoid of any human activity.
- Jim's first clue as to the state of London is a series of plywood boards on the street completely covered in missing persons notices, condolence messages and eulogies. A discarded newspaper reads that the city has been evacuated due to some sort of countrywide disaster which has cut Britain off from the rest of the world, causing Jim to believe that he is the only one left alive in the city.
- Jim encounters the Infected for the first time after entering a church. He notices several bodies packed into the church pews that appear to be dead, but when he calls out, some of them wake up. Jim is chased out of the church by a group of Infected, but runs across two survivors who help him by throwing Molotov cocktails at his pursuers. The burning Infected do not die immediately but they do charge into a petrol station, igniting the fuel and blowing the whole building sky high. Jim and his rescuers manage to escape into a tube station.
- The following day, Jim, Selena and Mark travel to Deptford to find Jim's parents' house. Jim finds his mother and father dead in their bed, apparently having commited suicide by overdosing on pills. A photo of Jim as a child is in his mother's hand. On the back of the photo is written a message:-
With endless love, we left you sleeping. Now we are sleeping with you. Don't wake up.
- Mark tells Jim about how he and his family tried to escape the country as the infection spread, how he and so many others had trampled over people who had fallen down in the mad rush to get on a plane, only to learn that there wasn't one.
- Two infected break into the house and attack Jim. Mark and Selena manage to save him and hack the infected to death with their knives. Selena also kills Mark when she sees a cut on his arm, fearing that the infected blood seeped into the wound.
- Jim and Selena enter a block of flats and are chased by a pair of infected. Here they meet Frank who, dressed in riot gear, holds back the infected with a shield. He beats one of them with a nightstick and pushes the other over the banister and lets him fall back to the ground floor.
- The group leave London and head for Manchester in a black taxi cab. They stop at a roadside diner along the way to take petrol from an abandoned tanker truck. Jim goes into the diner itself where he is attacked by an infected child. Interestingly enough, the infected child is still capable of speech as he shouts "I hate you!" when Jim pins him down. Jim then beats the boy to death with a baseball bat.
- The group approach the M602 blockade and see Manchester in the distance. The whole city is on fire.
- While Major West, his soldiers and their new arrivals are sitting down to dinner, an explosion is heard from outside the mansion, indicating that an Infected has set off a land mine.
- The soldiers mobilise outside as a large group of Infected charge towards the house. The soldiers gun down most of them and one sets off a mine and is thrown into the air only to fall onto another mine and get thrown up in the air in pieces.
- West finds Davis' body in a jeep and is then suddenly attacked by Infected. He manages to kill his attackers with his assault rifle.
- 28 days following the escape from the mansion, Jim, Selena and Hannah are only people left alive in the country after the Infected have started dying out due to starvation. Two infected are seen lying on a country road, severely malnourished and near death. As for the survivors, it is presumed they are rescued after a US aircraft flies over a cottage they are hiding out in, spotting the trio down below who have written a massive HELLO on the grass in linen.