Hit show going under the knife

Grey's Anatomy's Sandra Oh (Cristina Yang), Ellen Pompeo (Meredith Grey), and Katherine Heigl (Isobel 'Izzie' Stevens).

Like bones and dodgy body parts, expectations are promptly shattered on the set of Grey's Anatomy.

Where is the crew barking orders on their walkie-talkies? Where are all the beautiful actors floating past as makeup artists race after them? Outside, the only thing to suggest we're in La La Land are the rows of trailers; inside, it's the pair of rubber feet poking out from under a blue sheet in the show's OR.

As for the actors, Ellen Pompeo still has wet hair and co-star Katherine Heigl is eating - shock, horror! - a Danish pastry. This isn't the glamorous Hollywood scenario you'd expect.

But then Grey's Anatomy wasn't the hit show anyone expected. For the first two months of filming, a lifetime in telly terms, the cast had no word they would even go to air.

"We just assumed they hated us," says Pompeo, who plays the show's title character, Meredith Grey, "that they were going to take all the tapes and throw them in the trash."

Instead, Grey's debuted in the US to an audience of 20 million, and is now the third most popular show. In New Zealand, TV2 are proving their faith in it by giving it the Monday, 9.30pm timeslot to absorb Desperate Housewives fans. Last week, almost half the 18-39-year-olds watching TV were tuned into the drama at Seattle Grace Hospital.

Although the show's only awards to date are Sandra Oh's Golden Globe and Screen Actors Guild Awards for her portrayal of Dr Cristina Yang, Grey's was nominated in several categories at both ceremonies.

At which point it's tempting to ask - why? Sure, it has Patrick Dempsey - aka "Dr McDreamy", the show's resident George Clooney. But a bunch of bumbling interns performing gory operations while their superiors test their self-esteem? Didn't we get enough of that from (among others) Scrubs, Nip/Tuck and House?

"There's a humour to it, it's not so serious like a lot of medical dramas," says Kate Walsh, who plays Dr Shepherd's ex-wife, Addison. "Because of Ellen's voiceover it feels very personalised, and because they're newbies and struggling you see their personal lives, their vulnerability. It's a little more accessible. People see themselves in it too. It feels like a real workplace. There are a lot of cracks in the characters."

There are also a lot of references to sex. When the interns aren't falling into bed with each other - like Meredith and McDreamy - their patients are suffering injured nether regions and rectal exams. Hospital has never been so, er, sexy.

"Gender plays a big role in this," says Justin Chambers, whose character Alex enjoys a love-hate flirtation with Heigl's Izzie. "It's about sexuality and the relationships with the interns. In every episode there is something to do with the male approach to sex and the female approach or somehow there might be a dilemma with the patients physically. It's the style of the show and it definitely works, so we're riding that train."

Early this season Meredith and Derek's romance came to blows when his ex-wife took a job at the hospital, Cristina fell pregnant to Preston (Isaiah Washington) and naive George O'Malley (T.R. Knight) finally got some action, and an STD. An upcoming story sees an affair brewing between - wait for it - three of the women.

Grey's doesn't just use shock tactics in the bedroom. Every surgery is a vegetarian's nightmare, with fresh animal organs and blood.

"Once I had to like, lift a cow heart out of a scale," says Heigl, in horror.

"It was supposed to be engorged so it was really big. The artery was trailing down my arm."

In a recent episode, a boy with stomach pains was found to have 10 doll heads lodged in his gut.

"It was so disgusting. I had my mask on but you could still smell it and you're like, 'I'm going to hurl'. Two hours later you are still there and you're eating soup over the pig intestines. It becomes normal."

What some of the cast still can't get used to, though, is the show's monumental exposure. Oh complains of the paparazzi who took pleasure in documenting the end of her marriage last year.

"It is harder to go to the car wash and just be yourself."

But for Pompeo, 36, playing the self-doubting Meredith was a little closer to home.

"There are a lot of parallels in my life to this show," she says. "When I did the pilot I had no idea what I was doing, I had no idea what I was getting myself into. And I had never done a television series before.

"A lot of these scripts I don't necessarily agree with what my character does so I don't know if I'm doing the right thing with it. I don't feel I have a handle on anything, really. And I guess that sort of translates into what you see as Meredith hoping she is doing the right thing."

She takes comfort in something her Moonlight Mile co-star Dustin Hoffman told her when he starred in The Graduate. Throughout the film he thought director Mike Nichols couldn't stand him, that he'd made a huge mistake in casting him.

"And that's one of the most genius roles ever played," says Pompeo. "So I think a sense of self-doubt somehow translates into something very interesting."

For now, the biggest struggle is the workload.

The cast spend up to 14 hours on set, six days a week and Pompeo, a natural waif, has trouble keeping her energy levels up.

Today she looks as though she hasn't slept in a week.

"Because we are getting so much attention it makes all the exhaustion worthwhile," she says.