Not only is she getting fit, but Stewart is also dyeing her dark hair blonde and is going to embrace fake tan. The star said, ‘I think the hottest chick that’s ever walked the earth is Brigitte Bardot’.

The impending makeover is for her next starring role, in the film Cali. It’s about a couple ‘in the valley that gets involved with really strange people, really screw themselves over and become alienated, reinsert themselves into that world and try to survive. It’s really “Grindhouse”-y — extreme in every way’ the star told WWD.

But before she changes her look so thoroughly, we’re set to see her as herself, in the campaign for Balenciaga’s newest fragrance. For her part as the face of Florabotanica, designer Nicholas Ghesquière and photographer Steven Meisel wanted her to ‘just be comfortable’—no role-playing at all.

Stewart is the first to admit she’s a bit of a tomboy. ‘On a base level, the reason you want to wear a fragrance is because you want to smell attractive,’ said Stewart. ‘That in itself is a pretty mature idea, especially considering the teenager I was. I was never the one wearing my mom’s perfume and trying to be sexy. I was like hanging out with my brothers and doing the opposite of that’.

And yes, this is the first fragrance Stewart has liked enough to wear. ‘I’m very lucky that I like the fragrance, because I would have done anything with [Balenciaga designer Nicolas Ghesquière],’ she revealed. ‘And I’m a terrible liar.’ So much so, the star was relieved when she first smelled the fragrance and like it.

‘There is something natural about it,’ explained Stewart. ‘It’s very alive. I think that as a young person wearing it — considering that I’ve never worn a scent—it kind of puts you on this level of, like, ‘Whoa, check me out’.’

Ghesquière said he has wanted to work with Stewart since her saw her in the film Panic Room. ‘I remember thinking, ‘Wow, I would love to do something with her one day.’ She’s so Balenciaga.’

Stewart has not always been interested in fashion, but her collaboration with Balenciaga is changing her views.

‘I don’t want to sound pretentious—but I want to be part of this art project,’ she said. ‘I want to be around Nicolas when he gets excited about fabric. I want to see the look on his face when he sees me put on a dress.’

As for the fragrance itself, the idea for Florabotanica came from a collection Ghesquière created in 2008 that involved ‘nice’ and ‘nasty’ flowers—this scent is from ‘that garden’.

‘It’s more narrative, kind of a fantasy,’ he said. ‘So when I thought about the fragrance and the character that would visit that garden, I thought Kristen could be the perfect beauty and the perfect personality to represent that.’

The fragrance includes vetiver, amber and caladium-leaf accord, and a (hybrid) rose, carnation and mint accord.

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Did you know Kristen Stewart is the highest paid actress?