Jessica Biel: 'I fight against prejudice every day'

Jessica Biel's handler drops the bombshell when we're in the lift. "No questions about Justin Timberlake." The actress has been unofficially dating the "Cry Me a River" singer for the past year or so, but it's strictly off-limits. I'm here to speak to her about Easy Virtue, a film adaptation of a Noël Coward play in which she stars, but this is hardly an encouraging start. In our appointed hotel suite, a woman in a blue-and-white striped jumper sits in the doorway, presumably ready to eject me if the word "Justin" so much as leaves my lips. Meanwhile, two PRs wait in an adjoining room, one assumes, to listen to the conversation. I wouldn't be surprised if someone's hiding under the bed either.

When Biel eventually arrives – 25 minutes late and not a hint of an apology – she sits opposite me on a vast sofa, crossing one leg over another. Dressed in boots and a navy pinafore dress, with her blond hair scraped back, she means business. On the wall above her is a Perspex box full of butterflies, pinned for display. While it strikes me this is an appropriate symbol for Biel's situation, I wonder how she handles intrusive questions about her love life. "It just becomes awkward, as I have to say, 'I prefer to talk about the film because that's why I'm here.' You don't want to make anybody uncomfortable but at the same time you want to protect your life. Personal life and work life is completely different."

Coughing slightly, she stares right at me with her green eyes, and the conversation momentarily breaks down, both of us conscious of this elephant in the room that is her boyfriend. Changing tack, I ask how she copes with celebrity? "That is the most difficult aspect. It's weird, to be honest," she sighs. "People follow you all day long, taking photos of you walking out of offices and coffee shops. It feels strange and invasive. It's just a job and it's an amazing job, and has incredible perks... In my opinion, I just have a really great job and that's what it is for me."

You can't blame Biel for feeling this self-protective. At 26, her career is at what you might call a delicate stage. After getting her breakthrough in a series of genre movies – action (Stealth), vampire (Blade: Trinity), horror (The Texas Chainsaw Massacre remake) – she wants to be taken seriously. Being Timberlake's partner is hardly likely to help, but she maintains she's not one to frequent the Hollywood party scene. "Occasionally I do but rarely am I out and about at the cool place to be. I'm not nearly cool enough." Her life is "way more boring than you might perceive it to be", she says. "I'm working all the time and when I'm not working, I'm hanging out with my dog. Literally."

At least Biel is making headway in her ambition to move away from genre movies. The Illusionist, the 2006 period magic yarn in which she co-starred with Edward Norton, gave her some kudos. Enough to convince Stephan Elliott, the director of Easy Virtue, to cast her as Larita, a feisty American divorcée who remarries into a family of British aristocrats and proceeds to antagonise them. "It was exactly what I was looking for, something I could throw myself into where everyone is expecting me to fail," says Biel. "Internally, I knew I can do it. That's the joy of this business. Shaking it up. Surprising myself. Surprising everybody else. Otherwise people just put you in a box."

Pitting her against such British period stalwarts as Colin Firth and Kristin Scott Thomas (who play her in-laws), Biel gives a very good account of herself. Going toe-to-toe with Thomas, she trades Coward's quips and barbs with all the precision of a fencing master. "She's very different from me," she says of her character. "A really fantastic wit." So you're not witty? "I am, but not like her. I have comebacks but they're always an hour too late." Being a stand-up comic is not on the agenda then? "Never. That's like my nightmare." What about public speaking? "I'm not a big fan of that either."

With Biel contributing a version of "Mad About the Boy" to Easy Virtue's soundtrack, one of the film's biggest surprises is that the actress can sing. Despite beginning acting with amateur productions of Annie and The Sound of Music, until now she'd never sung professionally. "I can be decent at karaoke but I can also be quite rubbish at it," she laughs. Not least because she always chooses Queen's rather difficult "Bohemian Rhapsody" to sing. "I love the song so much, and I love the interlude where you head-bang by yourself in front of the microphone."

Claiming she has no interest in becoming a pop star, neither is she "fashion savvy", despite her swish D&G coat. "It's taken a long time for me to start to understand, start to even care, about what I'm wearing to go out in the morning," she says. "Now I do – because I have to, because you will be crushed by the press if you wear some crappy T-shirt and bad sneakers. I have changed a lot and now I think about it a lot more."

As clichéd as it makes her sounds, Biel is a small-town girl at heart. Raised in the shadow of the Rocky Mountains, in Boulder, Colorado, the daughter of an entrepreneur father and stay-at-home mother, she's a self-confessed theatre and soccer geek. Being a star was never on her agenda. But her striking looks – courtesy of her Choctaw American Indian heritage – meant she was always destined for more. After learning her craft in commercials, she received an offer to play preacher's daughter Mary Camden in family saga 7th Heaven, which became one of the highest-rated US series of the time.

By the time she was 17, she'd grown out of the role and was keen to leave, despite having a further two years to run on her contract. After posing semi-nude for Gear magazine in 2000, swearing like a trouper in the interview and proclaiming she wanted out of the show, she got her wish. She later admitted regretting the shoot, but nevertheless flirted briefly with a bad-girl image by turning up in the 2002 adaptation of Brett Easton Ellis's The Rules of Attraction. Not that this helped her career. "For a long time, I wasn't thought of as anyone with credibility in the film world," she says.

Not any more, though. She recently produced a 30-minute short, Hole in the Paper Sky, for her company Iron Ocean Films and hopes to go into production on a feature-length movie next February. She also is involved in Nailed, the new film from David O Russell. Biel plays a waitress who becomes unhinged after she gets a nail lodged in her head. The shoot was suspended just three days away from completion when financing fell through. The movie is still incomplete, and it's left Biel in limbo. "I will stop my schedule to finish it, no matter what I'm doing," she says, "But it's been a really bizarre experience."

Still, her recent roles have convinced her she's on the right path. "It's hard to find roles like Easy Virtue or Nailed," she says. "Complicated, interesting stories and interesting women... the bar has been set so high, I feel spoilt. It's the best thing that's ever happened to me but also the worst. Now I don't want to do just anything." Biel has a master plan: to diversify as much as possible so she can go back and make genre movies without becoming trapped again in that box. "Like Angelina Jolie – she can do anything she wants. She can do Wanted and she can do [Clint Eastwood's forthcoming film] The Changeling. She can do anything and nobody even bats an eyelash."

Now she's more selective and the days of her doing films such as The Texas Chainsaw Massacre are over. "If I had that opportunity now I probably wouldn't do it. But that was a perfect moment in my life and career, where I needed to take on something that would jump-start me." Does she still fight prejudice? She nods her head. "Yeah. I'm still fighting against it. Fighting every day." It's why she says the idea of marriage and children are too far-off to think about. "I'm career-driven right now," she says. "And I'm a little afraid of the idea of kids at the moment, even though I'm sure at some point I'll have them." Whether it will be with Timberlake is another matter.

'Easy Virtue' opens tomorrow. The soundtrack is out on Universal