John Boyega is talking about the day his world changed – and he knew everything would be OK. It’s not when he got the lead role in his first film, Attack The Block, aged 18, nor when he was whisked off by JJ Abrams to Hollywood for a mighty role in Star Wars. Not even when he earned his spurs as a serious film actor in last year’s Detroit, a shocking exposé of racism in the US police.

No, he realised everything was going to be just fine back in secondary school when he learned to use his hands. “I smacked a few people in the face. That was a glorious day. I was 14 or 15. I was on the 148 bus and I got to the bus stop and a guy that had been at our school was there with two of his friends. He wanted a new phone, so he thought he was going to get one off me. Anyway, to cut a long story short, he approached me with one of his friends and I made both their left eyes water. And I didn’t even punch. I slapped – hard. It was significant I slapped because that’s something a parent would do to their child.”

As Boyega tells the story, he seems to experience afresh the euphoria of learning to stand up for himself. “I felt great. Fantastic. Nobody touched me after that.” As a boy he was small for his age. Kids picked on him. Today, at 25, Boyega is a big unit – broad-shouldered, stocky, strong. He looks anything but a pushover.

As Finn in Star Wars he is puppyish, eager to please, endearing. In Detroit he is taciturn, observant, contained. In person, Boyega is a fascinating mix of the two – the boyish enthusiasm is countered with a resolute toughness. The second he walks into the south London pub to meet me, he is asked for an autograph. No, sorry, he says, politely but firmly, I am busy. It could easily come across as ungracious.

The next second he shows a generous side. When I head to the bar to get the drinks in, he stops me. “No, you’re in my manor, I’m paying.” He gets himself a rose lemonade. Boyega doesn’t drink alcohol. He can’t stand the taste, he says. We retire upstairs where it is empty. This is one of his favourite pubs because it is so quiet. But not today. Within a couple of minutes a young woman joins us at the table, uninvited. She is virtually sitting in Boyega’s lap and asks him if he would mind taking a picture with her boss downstairs, who is a big fan.

“I’m in a meeting, so I can’t leave.”

“I’m sorry,” she says. She stands up and goes.

“No, it’s all right, love. All right, take care.”

Does he get a lot of this? “No, I really don’t. I’ve never had that before. She really took a seat. Wow!” He bursts out laughing.

In the past, Boyega has insisted he is neither a role model nor a crowd pleaser. I tell him many famous people would have agreed to the photograph, particularly when being observed by a journalist. He’s not interested in that, he says. “I’ve been called an arsehole for saying no to pictures when I’m out and about. But I don’t care and the reason I don’t care is that I’ve never said no out of anger or dislike for the person or because I see myself as better than you.”

Boyega grew up on an estate in Peckham, south London, with his parents and two older sisters. His father was a preacher who ran his own church and his mother was a carer. As a young boy, he did not fit in at school, struggled with the work and found it difficult to keep up with others. “I was in the bottom set for everything. I was a bit of a nuisance in class.” In maths and English he would be thinking of films he had seen or dreaming of films he could be in – such as Star Wars. He was hopeless at sport (“Sport was more for the lads”) and went to a local theatre where he studied ballet, tap and contemporary dance. That probably also explains the bullying, he says. “Doing ballet in Peckham. You’re going to get whooped in the back of your head, yeah!”

How did his parents feel when he was bullied? “My mum and dad tried to get involved at various times. But it gets to a stage where teachers and family can’t help you. I’m sure my dad would have loved to bust a Range Rover through the school gates and bust up the whole school, but it wasn’t about that.”

Hold on, I say, that doesn’t sound very Christian. “No, he would never have done that,” Boyega concedes. “He’s a minister, but deep in your heart you want to do something for your child. And I handled it.”

Did he have many friends? “I wouldn’t call them friends.” Why not? “I didn’t see them that way; we were just students going to school. As soon as school is done, there’s nothing much in it. I had one friend from secondary school who went to the same college as me. That’s my boy Levelle. We’re friends today.”

Now, he says, he’s spoilt for choice. “I have five friends. My boys. We’re solid as a team. Nobody comes in and nobody goes out. We’re all going out tonight.” Most are musicians. “I don’t have close-knit friends in my circle that are actors.” It amuses him that so many people think actors are special. “It’s just a job at the end of the day, man. But we have to keep all that ‘Actors are special!’ so we can all get paid. Heeheeheee! It’s a way of tricking you guys.” Boyega has a deep voice and a joyous, high-pitched laugh like an attack of hiccups.

Before we meet, I have been warned that Boyega often thinks he is portrayed by the media as an urban street kid and that he thinks it feeds a racist stereotype. I ask him what he means. “Well, the [London] Evening Standard tried to tie me to the Damilola case and that’s insensitive as hell. They said something like, ‘He lived on an estate where guns and knives were rife.’ The fact is my estate wasn’t rife with guns and knives. That wasn’t the case. We had a beautiful theatre two minutes away from the estate.”

I had also heard he did not like to talk about Damilola Taylor’s death. But today he does so at length. He says it had a huge impact on him when he was growing up. “It was my first experience of murder [the schoolboys who killed Damilola were actually convicted of manslaughter] and of death. He was my sister Grace’s friend and I was always with my sister.”

Damilola’s family had only recently moved to Britain from Nigeria. Boyega’s father’s Pentecostal church was a hub of the local Nigerian community. If a Nigerian family moved to Peckham with children at the same school, Samson Adegboyega (John later shortened his name) would expect his family to support them. “When somebody comes from Nigeria for the first time,” Boyega says, “you look out for them. I was nine, Damilola was 10. He had a fresh African accent and he was getting picked on.” Boyega understood what it felt like. But, he says, it was harder for Damilola because he didn’t understand the culture.

Boyega and his sister were with Damilola shortly before he was stabbed. After school, Damilola had gone to Peckham library. On his way home, approaching the North Peckham estate, he was stabbed in his left thigh and it severed an artery. He collapsed in a stairwell and died on his way to hospital.

I keep thinking of what Boyega says about it being his first experience of somebody being killed. Lots of people never have that experience, I say. “Yes, and I was nine,” he says quietly. “The police came to our house because me and my sister were the last…” He trails off. “We were with him on the day. Before he got to the library my sister was like, ‘We should walk him home’ because it was already getting dark. But he was like, ‘I’m just going to pop to the library and then I’m going to go home straight from there.’ So we went home our separate ways. I think he had a crush on my sister. I was a bit uncomfortable with that.” Boyega smiles. “Then we got into the house. And a few hours later the police turned up at our door and all of a sudden we’re involved in an investigation and we didn’t understand what was going on.

“At the age of nine I found it a weird concept that someone is here one day and not the next. I didn’t understand what that truly meant. It was so big. I’d never heard of murders in London before then. A little kid running around with your packed lunch and your superheroes.”

Did the killing of Damilola leave him scared? “Of course it made you scared. From 2004 to 2009 knife crime was a huge problem. Even in church they would make announcements, ‘If anybody can drop anyone home because our kids can’t be on the streets.’ It felt dangerous on London’s streets. And not just in Peckham and Camberwell. Kensington and Chelsea – stuff was going down there, too. What scared me is that you don’t know who it’s going to be. I’ve seen white guys in suits bring out machetes. That was when I was going to school. The reality is you don’t know who can get angry and pull out a weapon. You just had to be careful growing up. My dad had to explain to me, look, when you see a commotion happen, whatever it is, just get out of the area.”

Boyega often refers to his parents, always admiringly. “My dad is the man I want to be. He’s the living example of who I’d like to embody. He is a very good, genuine man.”

Does your father think you are a good man? “He thinks I’m all right for the stage I’m at. I speak to him about everything. He knows there are certain elements that I need to work on, but I’m only 25.” What like? “More of an awareness of my spirituality. Not being controlled by emotions in the moment.”

What do you regard as your biggest failing? “The way I react to certain things. Sometimes somebody has a point, and I don’t have time, and I’m like, ‘What are you saying? Get straight to the point.’ I’m very direct and sometimes you have to realise people aren’t always like you.”

Especially in your business, I say. “Yeah, they like a little bit of bullshit soup.” How do you cope with that? “I don’t, I can’t lie.”

After school, Boyega went to college where he retook GCSEs in English and maths. By now he was determined to prove he could learn, and go to university. He discovered he loved reading, and maths started making sense to him when he began to read about the philosophy of it. Now he is passionate about education. “Is the system currently catered to the variety of brains we have? Hell, no. Stop teaching us bullshit. Teach us about tax, teach us about credit, teach us about opening a business, teach us about housing. A lot of people will lose out on opportunities because they don’t know.”

While still at college, he starred in Attack The Block, then he won a place at Greenwich University to do film studies. But after a year he dropped out to act full time, and in 2012 he met JJ Abrams in Los Angeles, while working on a Spike Lee pilot for a TV boxing drama that never got made. The Star Wars director had seen Boyega in Attack The Block, told him he loved it and promised to get him a part “in something”. Boyega thought he was all talk. “Thanks, mate, and sure,” he said sceptically. In 2014, after a seven-month audition process, Boyega was offered the part of Finn in Star Wars: The Force Awakens.

A few racists on social media objected to a black (former) stormtrooper. Boyega gave them short shrift, responding on Instagram: “To whom it may concern… Get used to it.” Boyega was astonished when people told him he should have reacted “with more grace and stayed silent”. That’s when he decided, if being a role model meant staying stumm when attacked, forget it. “I was like, be graceful? Are you mad? If anyone comes talking nonsense, I’m going to shut them down. You have to fight fire with fire sometimes.”

Boyega’s Finn has given Star Wars a new energy and sense of fun. Last year he appeared in Star Wars: The Last Jedi and he is signed up for the next instalment. It will be the first film without the heroic trio that have dominated the series – Princess Leia, Han Solo and Luke Skywalker. In December 2016 Carrie Fisher, who played Leia, died and now the characters Luke Skywalker (played by Mark Hamill) and Han Solo (Harrison Ford) have been killed off.

Boyega adored Fisher. “Great woman. She represented to me what I needed to see at the time – somebody who was just unapologetically herself, somebody who does not fit into any category. She was quirky, smart and intelligent. If you got her jokes, you felt intelligent because there was always wordplay – you’d really laugh because you’re thinking, ‘I got that!’” And he gets the giggles just thinking about it.

Last year Boyega showed off his range, appearing in the title role of Woyzeck, playing a squaddie driven to madness, in a radical reinterpretation of the 19th-century Georg Büchner drama at the Old Vic theatre. Again, he received positive reviews. Boyega says if he had to choose between stage and cinema, he would opt for the stage. But he is most proud of another film role from last year – in Detroit, he played Melvin Dismukes, a real private security guard who observed a racist killing by police officers in 1967 and was framed for the murder. Boyega plays Dismukes with a wonderful stillness. Why is the film so important to him? “Because it opened up another avenue of expression. When I was studying Melvin, I realised he was introvert. He didn’t express much, but on his face you can read the emotions he’s going through. It opened up another way of harbouring your acting skill, and the subtlety of the face is something I discovered I could do.”

Boyega has loved his success. Not least the freedom money brings. Look, he says, it’s obvious he doesn’t spend a fortune on clothes – he’s dressed in an Asos hoodie, Adidas tracksuit bottoms, white trainers and his sister’s All Saints jacket (“I like it, but I can’t close it cos it’s too small for me”). I find out what he likes spending money on only when I ask whether his parents still live on the estate. “Hell, no,” he says. “It’s the first thing I used my cheque for: to rehouse them.” Until then they had always rented their flat. “I chose the house for them.”

What if they had said, thanks, but we hate this place, son? That would never have happened, Boyega says. “When my dad preached, he would say he dreamed about material things, and he was scared about being too material at times: ‘But if anyone was to ask me as a human being, I’d love to drive a Jaguar and I’d love to have a house.’ He mentioned a particular area and said he’d love to have a house that was spacious, that had its own garden, that was private. White walls, wooden floors, spotlights, modern, clean and simple. So I got him exactly what he wanted.

“I told him he had an interview about Star Wars in a really nice house. We planned the whole thing. We had cameras there. It was a fake interview, but he didn’t know. I gave him the questions in advance and told him they were things like, ‘What does it feel like to have the best son in the world?’” Boyega bursts out laughing. “Then as soon as he came in, I went, ‘Dad, there ain’t no interview. This is your house. I bought you a house.’ He cried. He was in shock. I told my mum about the house a week before because I didn’t want the shock to be too big. They were really happy. I’d dreamed of it ever since I started dreaming – to get my parents a suitable house. I cried as well.” And now I’m starting to well up.

Did he get him the Jaguar, too? “Yeah, I did. The funny thing is, he won’t get rid of his old Range Rover.”

As well as starring in the forthcoming sci-fi blockbuster Pacific Rim: Uprising, he is one of the film’s producers. He’s taking his responsibilities seriously, he says, putting in a full shift – unlike some actor-producers he could name. “I don’t like the whole system of being a notable actor, then you just get the green light to go and direct or produce something. I actually want to learn the craft.”

His real ambition has always been to be a newspaper cartoonist. And he’d like kids – a few of them, please. I show him a story from a Nigerian website that says “Nigerian-British actor John Boyega looks like he’s found love with a quite pretty lady’’. He looks at the picture and shakes his head. “They always say that, man. Little do they know you’re in the friend zone. Heeheehee!” He has been in one long-term relationship, with a nurse, but he is drawing a blank at the moment. One woman he was seeing, he says, called it a day when she discovered he was in Star Wars. “A lot of women are like that. They don’t like it too loud. I’m very broke when it comes to love. If you put it in financial terms, money-wise I’m OK, career-wise I’m OK, spirit-wise getting there, love-wise, if it was money, I’d have like £320. No, £320.99.”

He looks at his watch. He has to meet his boys. I ask if he still has the wariness he had when he was young. No, he says. “I can go around and no matter what area it is, I generally get a lot of love. I can be in central London and a banker can come up and just go, ‘Oh, I think you’re great.’ Or I can be in Brixton and a group of people partying will come up.” And yes, he isn’t a huge fan of selfies, and will often refuse them, but he loves a good chat. “I was stopping by Sainsbury’s the other day, craving Jelly Babies, and there were a couple of schoolkids by the escalators. One of the guys had a BMX that was just like mine when I was growing up. I go, ‘Let’s see you pop a wheelie’, so he’s popping wheelies and I just chilled with them for 30 minutes, just talking.”

You may not always be nicey nice, I say, and you’re a reluctant role model, but it is obvious you are a role model of sorts. “Well, yeah,” he says. “I suppose you take inspiration where you can. As long as you don’t put an image of perfection on a person. People like to hope, man, which is cool, but add some wisdom to that. Know the person is a human being and that they can fail at times. Be inspired in the right way.” And with that he pops on his hoodie and his sister’s too-tight jacket, and heads off to hang with his boys.

• Pacific Rim: Uprising is in cinemas nationwide from 23 March.

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