WILDE AT HEART

When Olivia Wilde joined Fox’s hit show “House” at the beginning of last season, she played just one of a group of 50 interns competing for a job at Princeton-Plainsboro Hospital Teaching Hospital. Her name was similarly anonymous: Thirteen. Thirteen was among the ranks of such House-named characters as Cutthroat Bitch (Anne Dudek), Chief Defibrillist (Kal Penn) and Grumpy (Andy Comeau).

A year and a half later, Thirteen – and Olivia Wilde – is still hanging around the hospital. In fact, Thirteen – now known as Dr. Remy Hadley – has taken on a pivotal role.

“I assume they felt that anyone who stayed had to have an interesting relationship with House [Hugh Laurie]. That’s really what the show is about,” says Wilde, 24. “They are both very stubborn and smart, but they are different in a huge way: House hates ambiguity and Thirteen lives by it. They chose Thirteen more than they chose me.”

“House” is young Wilde’s biggest role to date, but it’s her third notable TV series, including NBC’s short-lived “The Black Donnellys.” She first appeared to TV audiences as another bisexual, Alex Kelly, on Fox’s guilty pleasure, “The O.C.” There, she had an affair with the show’s leading lady, Marissa Cooper (Mischa Barton), and it all caused quite the stir.

“It was very different to play a bisexual teenager involved in a relationship with a young, innocent girl like Mischa Barton’s character. Mischa had become such a phenomenon and that was why that ricocheted. That was a great moment for bisexual young women represented on a big show.”

Now, Wilde is playing out another controversial sort of relationship. Her character is romantically involved with neurologist Dr. Eric Foreman (Omar Epps), who is African-American.

“Bisexuality has been done dozens and dozens of times on TV and it still shocks people. They’ll talk about how they feel about it, whether it makes them feel good or weird,” says Wilde.

“But now that I’m playing a woman in an interracial relationship, I’ve found that people don’t want to talk about it. In the post-racial world, we aren’t supposed to consider what a difference in skin color or culture might mean in relationships. But what I really think is more interesting is confronting it.”

What Wilde mostly hears about her and Foreman is “oh, that’s so hot,” she says. “But they aren’t really that racy. They’re both professional doctors who work all the time.” As Thirteen goes about the serious business of healing people, her stunning looks are all but ignored.

If that storyline isn’t meaty enough, Thirteen last year tested genetically positive for Huntington’s Disease, a neurological disorder that also killed her mother. Thirteen – who has been a very private character up until recently – seemed fine living without knowing her diagnosis, but she finally took the plunge at the end of last season. Now, Foreman is helping her find a cure, albeit a little too aggressively. In the episode that aired Monday, Feb. 2, Foreman put her on a clinical drug trial without her knowledge. That drug gave her a brain tumor that temporarily threatened her life.

“Playing out that whole scenario makes me think a lot about what I would do if I had to face that choice,” says Wilde.

In real life, Wilde lives in Los Angeles with her filmmaker/musician husband of six years, Tao Ruspoli, 33, who also happens to be the son of an Italian prince, Alessandro Ruspoli. In 2008, the pair released a film they made together, “Fix,” which premiered at the Slamdance Film Festival last January.

The collaboration was a “brilliant” experience, Wilde says, and one that “makes you have a lot of respect for the other person, which in turn makes you attracted to them.

“It helps when you are with someone who understands your business. He understands if I come home at 2 a.m. and I just want to sleep for the next ten hours. And I understand too. He just had to shoot a film in Spain for a few weeks. I’m so grateful we got together before anything significant happened in my career.”

And Wilde’s TV life is nearly as absorbing as her actual one, she says.

“If you are on TV, you are really living this double life,” says Wilde. “You are facing obstacles on the show just like you face in life. It’s fascinating to play someone who has gone through such a dramatic year, but I would be happy to be on ‘House’ if all Thirteen did was show up every day and eat her morning muffin.”

HOUSE, Monday, 8 p.m., Fox

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