Beauty and the Beast: Stars Transform

It's not easy being ugly when you're Nicole Kidman, Halle Berry or Charlize Theron — but a gal's gotta do what she's gotta do to win an Oscar.

While television is obsessed with making over "regular people," Hollywood’s most gorgeous leading ladies are undergoing major make-unders to get Tinseltown's highest honor.

"Hollywood makes [actresses] look like normal people to give them an Oscar nomination," said Sam Saboura, a stylist for the television show "Extreme Makeover." "To get a serious role out of them they take away the glamour."

Normally dazzling lookers like Kidman, Theron, Berry, Naomi Watts (search) and Renee Zellweger (search) have all dressed down for award-winning roles. But why does Oscar go gaga for dowdy women?

“The Academy and Hollywood and even critics love performances where they can see all the physical work that’s gone into it,” said Michael Zam, a New York University professor and moderator the school's “Gold Dishers" panel on the Oscars.

And see it, audiences can. Theron famously gained 30 pounds for “Monster,” Kidman donned a fake nose and won an Oscar for "The Hours," Berry de-glammed for her Oscar-winning turn in “Monster’s Ball,” both Watts and Zellweger eschewed gloss for grime in their Oscar-nominated roles in “21 Grams” and “Cold Mountain” — and Zellweger also packed on pounds for "Bridget Jones's Diary."

It's long been a Hollywood joke that male actors need to play a mentally or physically challenged character to win an Academy Award, and insiders say the equivalent for women is playing plain.

"The things a man needs to do is play disabled. Dustin Hoffman in 'Rain Man,' Geoffrey Rush in 'Shine,' Daniel Day-Lewis in 'My Left Foot,'" said Jason Mittell, professor of film and media culture at Middlebury College. "[Women] have to show they are more than a pretty face and one way to do that is get rid of the pretty face."

Indeed, Theron's transformation into serial killer Aileen Wuornos (search), Zellweger's weight gain for "Bridget Jones" and Kidman's prosthetic nose used to play Virginia Woolf (search) in "The Hours" have provided endless fodder for talk shows and celebrity magazines — a fact Mittell finds disconcerting.

"You have a lot made of what these actresses go through in order to transform themselves,” he said. “No one ever talks about what they have to do to transform themselves into looking beautiful. Plastic surgery, Botox, three hours a day with a personal trainer.”

But Zam said Hollywood's beauty obsession isn't the only culprit. Audiences prefer seeing stars' flaws on screen.

"We love that they are beautiful, rich, glamorous and have access to jewelers and designers, but don’t like them to flaunt it," he said. "We like to know there’s something still human and they’re not too much like royalty."

Indeed, gossip circles have been buzzing over the possibility that Kidman was snubbed by the Oscars this year because she looked too fabulous in "Cold Mountain." While her character was supposed to be roughing it during the Civil War, her hair was flawlessly colored and her skin was radiant.

"She has a few dirt streaks on her cheeks, yet her eyebrows were perfectly plucked," said Zam.

On the other hand, "Zellweger really went for it," he said. For her willingness to get dirty, Zellweger got Oscar's approval in the form of a best supporting actress nomination, an award she's widely expected to win.

Still, Saboura of "Extreme Makeover," who knows what it takes to cultivate style, points out that even an actress' rugged look is as carefully planned as her red carpet outfit.

"They are all still wearing great, expensive clothes and their hair is 'perfectly' messy," he said.

E! gossip columnist Ted Casablanca agreed that women who let themselves be seen as less than perfect win accolades from critics and the public — but only up to a point.

"Audiences will go with you and ride with you and say 'Man, that’s just really good for her. That’s how I look in the morning,'" he said. "And then they think, 'Who am I kidding. She has 25 people on staff."

Poking fun at Hollywood's awe of actresses who forgo lip gloss and mascara, Casablanca added: "In Los Angeles, if you go out to Starbucks without makeup, you are considered brave."