“I DON'T usually step outside and analyse my career as a whole,” says Kristen Stewart, as if to warn me off asking her to do so. But it hardly matters when it’s down there in black-and-white: four years on from completing the $3.3 billion-grossing, five-film Twilight franchise that turned her into a global star, the 26 year-old Los Angeles native couldn’t be further from vampires, screaming fans and adolescent romance.

Rather, she’s reverted to her pre-Twilight years – when she was making indie marvels like Sean Penn’s Into The Wild. Last year, she won a prestigious César award in France – the first American to do so – for Olivier Assayas’ compelling Clouds of Sils Maria, playing a personal assistant to Juliette Binoche’s needy movie star, and co-starred in Still Alice, the harrowing Alzheimer’s drama that won Julianne Moore an Oscar.

An actress who values her privacy as much as her integrity, Stewart faced excruciating scrutiny back in 2012, when she was snapped kissing Rupert Sanders, her (married) director on Snow White and the Huntsman, a moment that ultimately drove a wedge between her and former boyfriend/Twilight co-star Robert Pattinson. Since then, she ducked from public view, taking eighteen months off to re-evaluate; the upside is, it circulated her back into the indie scene.

Working with a series of directors with “really unique perspectives”, the first is Woody Allen, whose latest is Café Society, a frothy 1930s-set comedy-romance that flips between classic Hollywood and gangster-run Brooklyn. The film reunites Stewart with Jesse Eisenberg, her co-star on Adventureland and American Ultra; he plays a wide-eyed East Coast native who arrives in Tinseltown, where he meets Stewart’s talent agency secretary Vonnie.

Stewart was immediately attracted to a character – an unconventional life-lover who has little time for the vapid celebrities circulating in her world. “[Her values are] not always going to fit into the conventional norms of what would make you a respectable young lady,” says Stewart, as if talking about herself. “And she is not affected by those things, she is not moored by that. And that’s modern, that is really forward, that is really progressive.”

This is Stewart’s first time with Allen, who has recently been employing Emma Stone as his go-to female. But her spiky presence – plus her natural rapport with Eisenberg – makes her perfect casting. Allen may be 80 years-old now, but his “sardonic approach to lofty, heady subjects” impressed the actress. “I love how his movies have a casual lightness; it puts you in a certain mood, so that when something comes at you that is meaningful and poignant, you’re caught off guard.”

Rather like Vonnie, Stewart has been surrounded by the entertainment industry for much of her life. Her father John Stewart is a stage manager who worked on this year’s Oscars pre-show. Her mother Jules Mann-Stewart worked as a script supervisor, which meant Stewart “grew up on a movie set”, eating the catering and popping up as an extra. Then, much to her parents’ dismay, she told them she wanted to be an actress.

“They didn’t really understand why. And I didn’t either. It was an arbitrary decision. It was just like ‘Yeah, I can do this. I can go on auditions.’ And they were like, ‘Do you realise what you’re getting into?’ My mom was like ‘I’m not going to be a stage mom!’ And unfortunately, she was…” By the age of 11, after becoming home-schooled, Stewart was acting opposite Jodie Foster in David Fincher’s home-invasion thriller Panic Room.

Chattering away in nervy, rapid-fire sentences, and sporting a cropped leather jacket, brogues and a slim-line black dress with a bow on the front, Stewart is far removed from the pouty figure she seems on red carpets. She wants to be open, on film and in public. “I don’t change who I am. I’m not a schizophrenic. What I want to do when I bring characters to life is to really reveal myself – there was a reason I was attracted to it. So I’m never hiding.”

Indeed, Stewart’s the sort that if you cut her, she’d bleed truth from her veins. Recently, she’s been open about her current relationship with Alicia Cargile, a former personal assistant; while some actors her age might hide their sexuality, Stewart isn’t one of them. “She has a certain emphasis on her own personal authenticity,” says Eisenberg. “She’s confident and she doesn’t try to ingratiate herself in order to get people to like her.”

Stewart nods in agreement to this. “If you’re being real, there’s a fairly undeniable confidence that you can harness.” Certainly, Stewart has bags of self-assurance.

Already, she’s gone behind the camera to shoot the video for Sage + The Saints’ song Take Me To The South and now a short movie called Come Swim. On screen this year, there are further films to come – including Olivier Assayas’ ghost story Personal Shopper and Ang Lee’s anti-war drama Billy Lynn’s Long Halftime Walk.

It is, she says, all part of a compulsion to create – something that only afflicts a certain tribe of “insanely insensitive” types. “Most people aren’t born with this impulse to write or make s**t out of clay or pretend to be other people, to act things out…some people are just happy within their lives, having families, having work that is satisfying for them.” Is it difficult to cope with? “There’s something there to protect for sure,” she grins, “because you’re different and you’re a little weird!”

Café Society opens on September 2.