28 Years Later ending explained and full spoilers: Who is Jimmy?

The film, which already has a stellar Rotten Tomatoes score and rave reviews, is full of some fascinatingly odd directorial choices and surprising narrative beats, and at no point is this more apparent than in the film's conclusion – which lurches quickly from a deeply poignant moment of mourning to a bonkers, cartoonishly violent showdown involving the introduction of a fascinating new character.

After a brief opening scene set back at the onset of the Rage Virus, the film picks up – surprise surprise – 28 Years Later, with the bulk of the action focused on 12 year-old Spike (Alfie Williams) who lives with his father Jamie (Aaron Taylor-Johnson) and sick mother Isla (Jodie Comer) on the island of Lindisfarne.

Their community is separated from the infected chaos of the mainland by a causeway, and towards the beginning of the film we learn that Spike must make his first venture away from the safety of the island for an important coming-of-age initiation.

From there, the film barely lets up, offering audiences a gripping – occasionally distressing – ride that eventually leads to the aforementioned enigmatic coda.

Seen the film and need those final moments recapped and unpacked? Desperate to know how it might feed into the already filmed sequel? Read on to have the 28 Years Later ending explained.

28 Years Later ending explained – full spoilers

When Spike had ventured to the mainland with his father for his coming-of-age initiation, one thing in particular had caught his attention: a bonfire he spotted while they were sheltering after being chased by a pack of infected.

When he arrives back home, Spike mentions the bonfire to his grandfather, who tells him that he assumes the man behind it must be Dr Ian Kelson – a former medical doctor who is reported to have become increasingly insane, building a strange ritualistic memorial to all those who have died since the initial outbreak of the Rage Virus.

Hearing that there is a doctor within walking distance, Spike spots an opportunity to get to the bottom of his mother's illness and so he decides to sneak away with Isla to the mainland to try and track down Dr Kelson – hoping he might be able to cure her mystery ailment.

On the way, they have an encounter with a Swedish NATO soldier named Erik Sundqvist and also discover a pregnant infected woman who gives birth to a newborn child that appears not to be infected. In the midst of a disagreement about whether to keep the baby, Erik is killed by an Alpha (the name for the deadliest type of zombie) before it is tranquillised by a morphine-laced dart shot by Kelson – who then greets Spike and Isla.

After introducing them to his large and rather eerie temple – which is constructed from the bones of those killed by the infected – he examines Isla and delivers some devastating news: she has terminal cancer, and does not have long to live.

He explains that the best course of action is to euthanise her, and so after the trio have some philosophical discussions about death – and Spike is afforded the opportunity to bid a tearful farewell to his mother – he follows through with this plan, before Spike places her skull at the top of the temple.

After another close brush with an Alpha, Spike then briefly returns home and leaves the newborn baby (who he has named Isla after his mother) behind, along with a note to his father and the other islanders.

The note explains that contrary to their beliefs, Dr Kelson is not mad, while he also outlines that he is returning to the mainland. Jamie attempts to run after him, but the high tide prevents him from reaching the mainland using the causeway.

Who is Jack O'Connell's Jimmy in 28 Years Later?

The film ends with one final scene which is set – of course – another 28 days later. We pick up with Spike back on the mainland just as he is being attacked by another horde of infected, and initially his odds of survival don't look especially rosy.

That is, until an unusual group of bandits come to his rescue, led by a character played by Jack O'Connell – who introduces himself as Jimmy and is decked out in a tracksuit and lots of jewellery.

In what is perhaps best described as a jarring tonal shift, Jimmy and his gang brutally dispatch the nearby infected using all sorts of weaponry – complete with decapitations aplenty – all while heavy metal music plays in the background.

On the face of it, this is good news for Spike – whose life was very much in danger before Jimmy and his followers arrived on the scene. But there are suggestions that there might be something a little more sinister going on that seems all but certain to feed into the next film – 28 Years Later: The Bone Temple – in which Jimmy seems certain to play a major role.

As for who exactly Jimmy is, his arrival recalls the very opening scene of the film – which saw a group of Scottish children watching the Teletubbies just as the initial outbreak of the rage virus took hold. Jimmy was the one child who survived this ordeal and has now grown into the man that greets Spike, and who appears to be operating some sort of cult.

There had been a couple of references to him sprinkled throughout the film: for example, his name had been carved on to the dead torso of an infected that Spike and his father had discovered on his first trip to the mainland, while a house in the background of another scene also includes graffiti mentioning his name.

These instances, coupled with the fact Jimmy appears to command a group of men who dress exactly like him, suggest that he has become a very influential figure – and we're willing to bet that influence might not all be good.

It's also worth noting that the character's name and outfit (blonde wig, colourful tracksuit, lots of jewellery) have caused many to wonder if he was partly inspired by Jimmy Savile, which only furthers the idea that we can expect some very nasty things from him in the sequel.

Writer Alex Garland told Variety of the character: "What he is from is the same thing that the entire film is from in a way, which is this film — and in a way the whole trilogy, if we ever get to make it as a trilogy — is in part about how we look in a regressive way to the past.

"Very simply, Danny and I grew up in an era where everything was about looking forward in some respects, and currently, for the last 10 or 15 years, we’re in an era that is very much about looking back. What the film is preoccupied with on some level is the way when we look back, there is amnesia, and there is cherry picking.

"Also, there are things that are misremembered. What the film is, if you look at individual characters, but you also look at the community that’s represented and the elements about the communication and the world-building is a mash of those things: Things that have been forgotten, things that have been cherry-picked and things have been misremembered. They’re smushed so together, which carries within it a kind of commentary."

We're very intrigued to see how all this develops, and especially how Jimmy might come up against Dr Kelson, in the sequel...

28 Years Later is now showing in UK cinemas.

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