The redemption of 90s It Boy Nick Moran

It's 12 years since Nick Moran starred in Guy Ritchie's gangster movie, Lock, Stock And Two Smoking Barrels. Since then he's co-written a West End play — Telstar, about Sixties gay pop producer Joe Meek — and turned it into a critically acclaimed film, which he directed. And yet the feeling persists that Moran is a bit of a geezer.

At the height of Lock, Stock's fame, he gained a reputation for bad-boy antics, such as punching a photographer unconscious at the premiere. He lived in a disused pub in Stockwell and dated Denise Van Outen and Sienna Guillory. "When you've been in the tabloids as a drunken It-boy," Moran says, "people automatically assume you're thick."

But now he has surprised everyone by directing a version of The Kid, Kevin Lewis's harrowing autobiographical bestseller about growing up on a poverty-stricken south London estate — not what you'd necessarily expect from Moran, who was once voted GQ's most stylish man.

Starring Rupert Friend (Keira Knightley's boyfriend), Natasha McElhone and Ioan Gruffudd, it's a no-holds barred account of child abuse, bullying and social neglect. You come out reeling. Who knew Moran was so interesting?
The Kid has been a hit with audiences at film festivals from Norway to Taiwan (where it was nominated for a Golden Horse). Beaten and starved by his addict parents, bullied at school and abandoned by social services, Lewis got caught up in the criminal underworld. But through the love of a good woman, he turned his life around (after the success of The Kid, he writes crime novels, and is a co-producer on the film).

"At screenings, women are weeping into their Ben and Jerry's and then coming up to me and Kevin afterwards like we're long-lost family," Moran tells me proudly.

All the violence is implied. "We do it with shadows, I nicked it from David Lean's Oliver Twist. I wanted to make a film that shows violence is an evil, contagious thing which permeates people's lives and ruins it — it's the antithesis of those cool films. It's ugly men rolling around in a car park stamping on each other. And Kevin's greatest achievement is that he broke the cycle."

Critics who feted Telstar may not like The Kid — it's uneven in places and wears its heart firmly on its sleeve. But it exposes some really important social taboos. We've probably all known a child at school who arrived covered in bruises or unfed. Back then people looked away embarrassed.

The NSPCC is backing the release. "I'm not making a film for critics," Moran argues. "And to be honest, in the editing suite I had to keep going back to the book because it sold a million copies and engaged with everybody. I kept thinking: What makes this book work?' and making sure I had all of its energy — irrespective of whether that made it slick or cool."

He asks a lot of his cast. In preparation for Telstar, lead Con O'Neill had to pile on 35lb in 10 weeks, eating whole Viennettas every night for tea — but it won him an an Olivier award. Rupert Friend, as Lewis, had to learn to box. "I met Rupert and thought, he was great. I didn't know anything about Keira, that's not on my radar. But I mentioned the boxing and he was happy to learn. So I phoned Steve Collins, middleweight champion of the world, and said Teach him to box'. Steve looked at Rupert in his floppy scarf and said Jesus Christ, he's a f***-ing handbag!" He got on the phone straightaway and literally booked Rupert into a fight. His agent went mental."

As Kevin's mother Gloria, Natasha McElhone was transformed into a drunken harridan with glasses and wonky teeth. "She looks like that every morning," Moran deadpans. "Seriously, it was my idea to just do a Charlize Theron in Monster and get someone beautiful and ugly' them up.

"Actresses always say they want to do this, and then when we put the offers out, to people who shall remain nameless, it was amazing how many sent the script back. But Natasha bit straight away. At first she was a little bit hesitant, she was heavily pregnant, but then I showed her a screening of Telstar — she had to run off afterwards because she started having contractions — and she loved the movie. And she really went for it."

I ask him why he thinks Gloria was so appallingly cruel to Kevin, out of all his siblings. "Because she's jealous," he says quietly. "Quite simply he gets more attention from her husband than she does."

Moran, 40, lives in a Georgian house in Fitzroy Square (neighbours include Ian McEwan and Griff Rhys Jones and Guy Ritchie is about to move in too) but he knows all about living in challenged circumstances. "I was brought up on a tin-house council estate, two rows behind South Oxhey estate, just north of Harrow and Willesden."

He says there was a strong National Front presence. Things were constantly torched and stolen. "I know that family in the film. They weren't called the Lewis family ...I won't embarrass them but they had half a dozen kids and a dad who didn't work because he claimed to be agoraphobic and a violent mum. So I understand that section of the film endemically."

Although Lewis actually grew up in New Addington, Surrey, Moran filmed a lot of scenes on South Oxhey because he knew the area and the community trusted him not to misrepresent them. "I curried a little bit of favour because I could say: I went to school with your sister.' No slur on the people of South Oxhey but the reason we didn't get windows bricked was because I went there as an ex-pat and gave everybody jobs as extras. It was a lovely little exchange."

The film is unapologetically Left-wing. Moran grew up in the Eighties and shows us scenes of greedy City traders "who run everybody into recession" and estate agents fleecing vulnerable individuals such as Kevin Lewis.

"I remember this quote from Margaret Thatcher along the lines of a young man in his twenties on a bus is a failure'," says Moran, visibly furious.

Today many of the kids he grew up with are dead or in prison. Why did he survive? "I always smugly believed there was something better a bus ride away. I was in school plays and bands."

He left college at 16 and moved out of home, lying about his age to get into Mountview drama school, where he read Pinter and Brecht; he got himself educated.

When Lock, Stock took off, he'd been acting for 10 years (he was in the West End version of Blood Brothers for a while). He'd be on television one night, emptying the bins in Haringey the next. But the success of the film took everyone by surprise. He hung out with Sting (who played his father in the film) at his Manhattan apartment, met Tony Blair and the Dalai Lama.

"I was like a kid in a sweetshop with a £10 note," he confesses. "Imagine coming from that estate to suddenly being on Hugh Hefner's boat. I was the incorrigible guy making all these terrible faux pas."

Today he still possesses manic energy and radiates warmth (he arrives bearing gluten-free gingerbread as an apology for being late). Keen on the sound of his own voice, nevertheless when he is working Moran listens and soaks up information. "I sleep in my campervan. I don't drink, I don't socialise."

He hasn't given up acting — he's playing snatcher Sabior in Harry Potter and the Deathly Hallows. But directing is a passion. You have to like a man who says he spent a year watching rom-coms on the sofa with his girlfriend Vicky to capture the same emotional intensity for his own work. "I've seen them all — He's Just Not That Into You, PS I Love You."

The Kid is being sold as "Slumdog Millionaire set in Croydon". "But then an American agent said to me [he mimics a bruiser accent], It's like Precious with skinny white people'."

Moran wants me to stress that it's not just a misery memoir. "It's a fairytale basically about someone with a good, true heart overcoming extreme adversity because they're kind.

"You have a witch, a fairy godmother, love conquers all. The reason the book was a success is because it's shamelessly honest. It's about one man's little journey into light."

The Kid is released on September 17.