Diary of a Teenage Girl star Bel Powley on style, sexism and becoming a star

Early on in our interview, I mispronounce Bel Powley’s surname and she swiftly corrects me. ‘It’s Powley, like power!’ the 26-year-old grins, round, blue eyes popping cartoonishly.

Fair enough: power, of the star variety, is something Powley most certainly has. This year is looking like a watershed for Powley on screens big and small. First came the BBC’s Informer, the rather excellent Bodyguard-esque drama that finished on Tuesday last week, in which she starred as a counterterrorist officer alongside Paddy Considine. Next up is White Boy Rick, Yann Demange’s true-story tragedy about drug dealers in Detroit, starring Matthew McConaughey, which hits cinemas next week. Basically, it’s the biggest season yet for Powley, whose star has been on the ascendant since her breakout role as Minnie in 2015’s cult indie flick, The Diary of a Teenage Girl.

Powley seems the definition of relaxed: high-waisted jeans unbuttoned (‘they’re quite tight’) and pearl-studded Gucci loafers kicked off; voice cracking into breathy squeals of joy when the make-up artist, who turns out to be a magician on the side, shows her a card trick. But don’t be fooled: she is bursting with ambition. ‘Twenty-six feels quite old,’ she says. ‘I feel like I’m on the wrong side of 25 now, like I’ve gotta achieve all the things I want to achieve really, really soon.’ That’s pretty punchy for someone who didn’t even want to be an actor as a child and only took on her first television role in order to fund her university degree.

Powley was born in Shepherd’s Bush, the daughter of an actor (Mark Powley, whose CV includes The Bill, Casualty and Hollyoaks) and a casting director (Janis Jaffa) who, despite their jobs, were pretty horrified when their daughter was cast from her drama class as the lead in the CBBC show MI High at the age of 14. ‘They were like, “Oh God, no, we thought she was going to be the academic one and go to university.”’ For her part, the ‘super geeky’ Powley thought she was being ‘savvy by doing this little TV show and saving money to go to uni’. But then she landed a role in her first theatre production, Polly Stenham’s Tusk Tusk at the Royal Court, and the acting bug kicked in full throttle, with another Stenham play and a production of Tom Stoppard’s Arcadia on Broadway following when she was 19. After that, she was supposed to embark on a degree, but ‘kind of kept deferring... for three years’. During those three years, she was steadily notching up TV parts (Benidorm, The Bill) before landing her breakthrough role in Marielle Heller’s The Diary of a Teenage Girl. She was 22. Mr and Mrs Powley gave up any hope of their daughter going to university.

Her role as 15-year-old Minnie, coming of age in LSD-streaked 1970s San Francisco and having an affair with her mother’s boyfriend (played by Alexander Skarsgård), was lauded by critics and, to this twenty-something girl, felt astonishingly, viscerally relatable on its release three years ago. I’m not alone. ‘I’d never felt so in touch with and so close to a character. I’ve never felt that again. I felt like I was Minnie: I’d had similar experiences to her, I could relate to everything that happened,’ says Powley in a rush. ‘Since then it’s been a weird learning curve, realising that it’s not like that on every single project.’

Like, for example, her latest role in White Boy Rick. The film tells the miserable story of Rick Wershe Jr, the 14-year-old who became the FBI’s youngest-ever informant and was then abandoned by his handlers. He was later arrested for dealing cocaine and served a 30-year life sentence. Powley describes it as a film that works on ‘the macro and the micro’, a relatable coming-of-age story that also has ‘umbrella issues: gun violence, drug use, the war on drugs, the failure of the justice system, the underbelly of society that exists in capitalist countries like that’.

In it she plays Rick’s drug-addled, girl-from-The-Ring-haired sister, Dawn. ‘Playing a drug addict is a tough one. You’re limited to your research, unless you choose to go and take loads of drugs, which I didn’t think was the most sensible choice.’ So her performance — less Trainspotting, more a scared little girl fighting serious internal demons — required a lot of internet research. ‘There are actually a lot of videos on YouTube of people smoking crack,’ she says, grimacing.

In one scene, Ricky’s car gets stolen from outside a diner, and he and Dawn race out, guns blazing, to try to stop the thief. It was the first time Powley had ever been around a gun, let alone fired one. ‘It’s so mad. All Americans have probably fired a gun one time in their lives, or held one. We had to go to a shooting range behind some weird old train tracks where the ground looked like it was all gravel but was actually all shells.’ The rough Detroit accent was another challenge. When rehearsing the film’s opening scene, in which Powley runs out in the snow in her underwear, the Friday before filming started on the Monday she was ‘so nervous that my accent went out the window. Yann came up to me like, “Bel, you still sound like you’re from London, are you okay?” I was like, “Oh, God, I’m gonna get fired...”’

There were no such issues with Informer, which Powley excitedly says ‘feels like it’s portraying real London, like it shows how this city really breathes and exists’. It was the first time she had filmed in the capital, which meant that for the first time in her screen career, ‘I got to go home to my own bed and my boyfriend and my friends’. Powley currently lives in Kensal Rise with housemates and ‘a lot of houseplants, which are kind of like my children’. Given her normal globetrotting film schedule she is an avid dinner-party host when at home, although admits: ‘I’m quite slapdash with my cooking, guessing how much 100 grams is. My boyfriend goes, like, by the recipe, by the book.’

That boyfriend is fellow actor Douglas Booth, whom she met on the set of the Mary Shelley film, A Storm in the Stars, in 2016. They pop up on each other’s Instagram feeds continually: in Italy on holiday with Powley’s sister, Honor; in Amsterdam for the opening of Soho House; at a Thanksgiving dinner with Luke Evans. In case there was any doubt of their relationship, Booth’s face is also the background on her phone and there are passport photos of him lodged in her phone case — but she’d ‘rather not talk about it because it’s not that interesting’.