Mariah Carey Serenades Crowd At 'Hills' Premiere Party

Plus: First daughter Barbara Bush helps usher in new episodes of the hit reality series.

NEW YORK — The scene Monday night inside Manhattan's Gotham Hall recalled a sweet 16 party. Bubbly young girls by the dozens — decked out in high heels and skirts so short, you'd have thought they were swatches — lolled across cozy chaise lounges, quietly ogling the night's guests of honor: Lauren Conrad, Audrina Patridge and Whitney Port, the stars of MTV's "The Hills."

The gang was on hand for a special party, celebrating the return of the hit reality series, which picks up right where it left off: with Lauren on her way to Paris. (Lauren, Audrina and Whitney discuss fame, privacy and life after "The Hills" here.)

While the rest of America huddled around their televisions for what was the first of 10 new episodes (think "season 3.5"), Conrad, Patridge and Port watched the action as it splashed across a mammoth screen, alongside their fans and a couple of big-name guests — one of whom caused a lot of head-scratching. Seated at a table without any visible security was Barbara Bush, the 26-year-old daughter of the president. She laughed and smiled throughout the premiere episode and seemed to be at home amid all the hoopla.

But the highlight of the party — at least for the "Hills" starlets — was the arrival of Mariah Carey, who performed a small set that included "I'm That Chick" and "Touch My Body," new songs from her forthcoming album, E=MC2, which is due April 15.

Wearing a black skirt with a gold top, Carey also performed "We Belong Together," which the audience sang back to her. She was whisked offstage after the performance to resounding cheers.

"I've always been a huge Mariah fan, and she's just so beautiful and talented," Conrad said, before Port added that she basically grew up listening to Carey. Patridge, whose nude-photo scandal made headlines last week, called Mariah "such an amazing singer" and complimented her on her performance.

Once the episode began, the crowd alternated between moments of high-pitched delirium and hushed rapture. Clearly, those gathered there had their allegiances (a smattering of boos could be heard when Heidi Montag and Spencer Pratt appeared on the big screen), and having Lauren, Whitney and Audrina at the center of it all certainly didn't hurt.

But the "Hills" stars weren't used to watching themselves onscreen — or at least on one this big.

"I've never seen myself on such a large screen before, so that should be interesting," Conrad said before the premiere. "It's always cool to watch it with people who watch the show, to get feedback and their reaction. I'm excited for people to see [my experiences] in Paris, and there's some fighting [this season], which is never fun for me to see."

"It's actually horrible," joked Port, who shared whispers with Conrad and Patridge throughout the episode. "It's like, 'Oh my God — I didn't know I had that on my face, and that on my face.' But you can't be vain."

"There are so many people here supporting us tonight, it gives me butterflies," Patridge said. "And on that big screen, our faces are really big. I'm just enjoying it, and I can live [vicariously] through [Conrad's and Port's] experiences in Paris. There are lots of transitions being made [this season], from jobs to guys to moving."

Of course, no one wanted to dampen the evening's mood by discussing Audrina's controversial pictures. When asked if the last week had been hard on the girls, Conrad's face sunk, and she immediately blurted out, "I'm not talking about that," before being ushered away by her publicist.

(We might not have those super-scandalous pics, but our Newsroom blog did dig up some pre-"Hills" footage of Audrina walking the red carpet in a bikini on the arm of a now-embattled designer. Check it out!)

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