The last time pop star Mariah Carey had a key role on the big screen was in the notoriously awful “Glitter” in 2001. But her performance in the upcoming drama, “Precious” has drawn a much different reaction from the critics: praise. Director Lee Daniels removed every bit of “glitter” from her physical appearance for the film and transformed her into a dowdy, unglamorous, non-make-up-wearing welfare caseworker - the very antithesis of a diva.

Why would she agree to all this? I put that very question to her at the film’s red carpet premiere Sunday night at Grauman’s Chinese Theater in Los Angeles.

“I just loved the book 'Push' that 'Precious' is based on and read it a few years back,” she says, “And I was just like, if this gets made into a movie - and I know Lee Daniels can do it right - if I can just be a part of it, they can put bags under my eyes and as many mustaches on me as they want, and hideous hairdos, and it is what it is, but it comes from inside and they stripped all the layers and [helped me] become the character.”

One of my colleagues in the press asks, "Was this performance a career milestone?"

“I had one film [Glitter] that had me under the stone! (laughs) I didn't realize that you really have to be selective with the people that you work with and you have to have that support system and you have to work with people who you think are geniuses and Lee Daniels is a genius in my book.”

“Precious” opens in limited release this Friday, November 6th.

You learn a lot about diva-dom when you’re standing 10 feet away from a Mariah Carey performance, as I was Friday. Everything is done with extravagance: the lashes, the Christian Louboutin boots, the skin-tight dress revealing ample cleavage, the long tresses blowing in a gentle breeze provided by strategically placed fans. Check out the scene:

At one point, when Carey’s one-of-a-kind voice reached for the crescendo of Foreigner’s “I Want to Know What Love Is,” a sudden burst of gold streamers showered her and her backing choir.

Ridiculous? Well, sure. But it’s also spectacular.

From the moment Carey stepped onto the “Today” show stage in Rockefeller Center early on Friday morning to perform a few cuts from her new album, “Memoirs of an Imperfect Angel,” her presence hit you like a perfumed hurricane. Fan or not, at close range Mariah Carey is utterly beguiling.

The best-selling female artist of the ‘90s, Carey has sold a whopping 160 million plus albums worldwide during the course of her impressive, if at times rocky, career. She also pulled off one of the most successful comebacks in music history, with her post-breakdown album “The Emancipation of Mimi” becoming the top seller of 2005 in the U.S.

And with the glow of her 18-month marriage to fellow singer Nick Cannon still obvious (they cuddled and kissed on stage after Friday’s set), as well as the positive reviews she’s getting for her acting role in the upcoming film “Precious,” Carey looked happy.

When we stepped onto her massive tour bus for an interview, it was clear she was a little drained from her “Today” performance, but she was perfectly pleasant and un-diva-like.

I was just getting Carey, who turns 40 next year, to talk about the significance of the word “imperfect” in her album title, when I was told to wrap it up.

Seriously? We were only 40 seconds into the interview.

Apparently the bus had overstayed its welcome on 49th Street, and the police outside were getting edgy. Mariah’s caravan had to push off.

Seconds after she shook my hand and said with sincerity that she wished we could’ve chatted longer, my cameraman and I found ourselves back on the street with scores of screaming fans.

Feeling slightly dejected, we watched as Carey’s chariot – all white and adorned with larger-than-life images of the same scantily clad Carey you see on her album cover – drove away.

No, Mariah isn’t perfect. And maybe that’s why we can’t stop looking.

"America's Got Talent" host Nick Cannon was spotted hanging at the White House Tuesday morning. The actor/hip-hop singer/ producer, who was accompanied by a small entourage of four, said he hadn't seen the President. Why was he here? Cannon was taping promos for the season premiere of the show. In fact, later he was positioned in front of a camera on the North Lawn next to CNN yelling loudly "America's got talent! Season four! Begins now!" "The wait is finally over! This is America's got talent!" "Tonight season premiere! The show that turns ordinary people into superstars!" Facing the same challenges White House correspondents regularly experience, Cannon, was forced to do several takes of the teases, stopping and starting because of noisy hammering from construction across the street.

There was just one question almost all the White House photographers asked Cannon, "where's Mariah?" Indeed, there was a lot of finger-pointing and excitement among some who referred to him as "Mariah Carey's husband." So I asked Cannon myself, if she'd be coming. Cannon said Mariah was at home and doing great. You could see the disappointment on so many faces.

Cannon, like many tourists, went to the White House briefing room, stood behind the press secretary's podium, and mugged before cameras. Later he went to the press' back lunch room where he munched on a vending machine sticky bun. Cannon seemed thoroughly excited to be at the White House, despite the fact many in the press corps who spotted him, kept asking, "isn't that Mariah Carey's husband?"