Adolescence ending explained: Why did Jamie kill Katie?

The ending of Adolescence, which sees Stephen Graham's character Eddie return to the room that once belonged to his 13-year-old son Jamie, before his child murdered a young girl, is something the actor always knew would close the four-part series.

"That was an idea we had at the beginning," he told RadioTimes.com. "Me, [director] Phil [Barantini] and Jack had this idea that we'd end it in the room, because of where it all began.

"And also that thing of 'you never know what's going on behind his door', so to be immersed in that room, where this wonderful boy was born, and to see his pictures on the wall, and his pens and his pencils and all of those things in that room, but also the room where the mindset was created for him to commit such a horrendous thing."

But it's what happens next, after Eddie enters Jamie's room and takes it all in, that will stay with you long after the credits have rolled. Read on for everything you need to know about the ending of the Netflix drama.

Adolescence ending explained: Did Jamie kill Katie – and why?

While initially Jamie insists he's not guilty, the close of episode 1 sees him and his dad Eddie (Graham) being shown CCTV footage in which Jamie pushes Katie over in a parking lot and repeatedly stabs her.

Rather than an exploration of whether or not Jamie committed the crime, what follows is an examination of why he would do such a thing.

As the series unfolds, it becomes apparent that a combination of factors have led to Jamie murdering Katie, including his lack of confidence, bullying at school and radicalisation through online incel propaganda.

Graham and Thorne previously revealed that the drama was inspired by shocking real-life events and by the growing knife crime epidemic in the UK.

Speaking about what they hope viewers will take away from Adolescence, Tremarco said: "It's to make people aware because even when I first read the scripts, I had no idea what an incel was. I had no idea that this was happening, and with kids as well. [We want] to educate everyone – parents, children, because it's happening with children.

"And also that level of misogyny towards young girls and women, and just on a computer that our kids can get sucked into, that you can have no idea about, it opens difficult conversations that need to be had."

Graham continued, discussing "how much the world has changed" for children and their guardians.

"We think he's safe in his room... that home is the microcosm, and that's where you should be safe. That's where he's raised and that's where your security is. But through the telephone, through the internet, there's a whole macrocosm out there of stuff that we have no control over as parents."

In the final episode, we see Eddie and Manda ask themselves questions about whether they should blame themselves for what's happened and how responsible they are for Jamie's actions.

"And we were never saying one particular person is to blame, or one thing is to blame. It's surely, as a society, we should look at this, and we should all be accountable," Graham added.

"The children are our future. We are all accountable for raising this next generation – parents, schools, government, community, society as a whole. We all should be accountable... because there was a few incidents, there were a good few incidents why this idea came to my head. And it hurt my heart that young boys, they're not men, they're young boys, are killing young girls.

"So it's just creating conversation in the homes, because I think it’s imperative for the future of our nest generation."

What happens at the end of Adolescence on Netflix?

After Eddie sits on the bed, he breaks down, unable to control his emotions as tears stream down his face. Eddie then takes his child's teddy bear and tucks it beneath the covers, as he would have Jamie, once upon a time.

"I'm sorry, son," he says. "I should have done better."

"Phil just said to me, 'I'm going to leave a teddy bear on the bed,'" explained Graham. "And I was like, 'OK, all right.' And just instinctively, I kind of took the teddy bear as the last little remnant of my boy."

It's an extraordinary moment, courtesy of that particularly tender detail, but also the intense outpouring of emotion from Graham, who revealed the "secret" that helped him to inhabit that headspace.

"The take we actually used was... the last take of the whole thing, and on that final take, my wife [Hannah Walters, who is his producing partner, and also plays a teacher in Adolescence] and my two kids were there as well. And so when I go into the bedroom, what they'd done was they put some pictures on the wardrobe, and it said, 'So proud of you, we love you, dad.' And it was pictures of my two kids, Grace and Alfie, who I adore.

"So that kind of sparked that last, final scene in that moment as well while I was thinking of him [gestures to Owen Cooper, who plays Jamie], who I've had the most amazing experience with."

Graham also praised Christine Tremarco, who plays Jamie's mum Manda, for helping him to produce some of the best work of his career.

"Sharing that whole run up to that scene with Christine, who is phenomenal," he added. "She's unbelievable. And we've known each other for a long time, so there's a real trust there.

"So to be able to bear your soul in that respect... [and] go into that room and finish it like that, for me, it was wonderful. And what we really wanted to show as well is that inside Eddie's heartbroken, he's heartbroken. He's tried to keep it all together, but inside he's got a broken heart, and he doesn't know how he's going to mend that."

What happens to Jamie at the end of Adolescence?

While the series doesn’t show us Jamie’s trial or reveal his sentencing, his decision to plead guilty heavily implies that he'll be given a life sentence in prison, as is mandatory for people under 18 convicted or pleading guilty to murder.

Read more:

• Adolescence age rating – how old do you need to be to watch?
• Adolescence soundtrack: Full tracklist for Stephen Graham Netflix drama
• Stephen Graham and Adolescence director explain why Netflix crime drama is filmed in one take

Adolescence is available to stream now on Netflix. Sign up for Netflix from £5.99 a month. Netflix is also available on Sky Glass and Virgin Media Stream.

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