There is nothing cool or intimidating about Huntington-Whiteley, she’s just a knockout.

Eight years into her career and still only 25, Huntington-Whiteley is now a big enough name to carry her own lingerie line for Marks & Spencer. “Six months ago, I could walk down Oxford Street and be completely anonymous, but yesterday I was starting to get the tap on the shoulder, ‘Hello, I’m a big fan, can I get a picture?’,” she laughs, “and it’s fun.” Her fame was kick-started during her time as a Victoria’s Secret model (a job that guarantees wall space in boys’ bedrooms the world over). Since then she’s been the face of the Burberry Body fragrance and Marks & Spencer’s Autograph range, and starred in Transformers 3 as Shia LaBeouf’s girlfriend (ie, the ultimate fantasy girl), in the process establishing herself as the best of a new sizzling-hot yet surprisingly wholesome breed of model. Slender and curvy rather than skinny; clean-cut and healthy, not rock-chick jaded; naughty enough to do the lads’ mags, feature occasionally in lingerie enthusiast blogs, but classy enough to make the cover of Vogue.

In real life she is all about looking gorgeous and glossy and uptown girl. You won’t catch her dragging on a fag outside a club at 4am, flashing a lot of cleavage, wearing Dr Martens and denim shorts or multiple piercings. She does have a tiny tattoo on her wrist, but it’s the delicate outline of a heart. She is the definition of a sex bomb, and yet you can imagine her baby-sitting your children. As a result, teenage boys want to marry her, girls want to be her (“For me, it is always the biggest compliment when a girl comes up and says hello, more so than a man”), and grown-up women admire her. That breadth of appeal is no accident. Not so long ago, models lived on cigarettes and champagne and didn’t think about tomorrow, but Huntington-Whiteley is one of the post-Gisele generation who see modelling as a long and lucrative game and their bodies as an investment. “I love Gisele. She has such a healthy image and she has made herself into a brand. I guess I try to think of myself as a business. And I want to go to work.”

Ask her what it takes to be a good model and she doesn’t hesitate: “You have to have a strong personality, to be able to pick yourself up and dust yourself off, and you have to find your voice pretty quickly to be able to say no and stand up for yourself.” These days, she finds people treat her with a lot more respect than they did at the start of her career, when she was “pushed around” and told she was both too short and too fat. “It’s not because times have changed, it’s because my position has changed,” she says with an arch of an eyebrow. Being in a position to call the shots, and then calling them, is what it is all about. “When a woman wants something and she goes about it in a tough way, a lot of times she gets branded a bitch. That pisses me off, because when a man is firm, he’s just doing his business. But I definitely don’t go around stomping my feet and shouting.”

Business, in the immediate future, means frequent trips to Namibia, where she is filming Mad Max: Fury Road, starring Tom Hardy and Charlize Theron. “It’s an ensemble cast,” she says briskly, when I ask about the size of her part, and more searching questions are off limits. Also off limits is her two-year relationship with the actor Jason Statham, with whom she shares a house in Los Angeles, though she will say he loves her undies and she can’t wait to be reunited after five weeks apart. Life in LA means going to the gym every day and cooking Sunday roasts for friends. “It’s much more geared up for fitness and health, and the sun is up every morning, so you want to be outside. It’s not really a night-time place.” See, not so much as a whiff of decadence. What does she do that people would never imagine? “I like to clean my bathroom.”

There is just one possible downside to being Rosie Huntington-Whiteley and that’s the dazzle factor: people, especially men, not being able to see beyond the lips and the legs and the whole Victoria’s Secret bit. Has she ever worried about that? “I got through all of that a while ago,” she says. “Now, I just try to be who I am and stay true to myself.” Which isn’t going to solve anything, obviously, but no point telling her that.