Meester has an elite role as a rich teen in the new show 'Gossip Girl'

NEW YORK - 'Gossip Girl' star Leighton Meester is cooling her heels.

No, not the black patent heels she'll be perched high atop for her first scene of the day. That's hours away.

Right now, she's passing time, barefoot, in a trailer parked off bustling Madison Avenue in midtown Manhattan.

It's about 7 a.m. on a bright, sunny July morning, and Meester is bright and sunny, too, prepared to make herself at home until she's summoned.

White noise wheezing from the trailer's air conditioner does a pretty good job masking traffic outside, 'but I keep realizing: I'm on the street in a box!' Meester laughs. 'Like they say: The acting is for free. I get paid to wait.'

True enough. But career-wise, Meester's wait could be just about over. Born in Marco Island, Fla., and raised in New York before moving to Los Angeles, the 21-year-old actress got her start as a child model. She has appeared on series including 'Shark,' 'House,' '24' and 'Entourage.' Two seasons ago she was a regular on the short-lived NBC drama 'Surface.' She's made several films.

But now she's stepping into the high-profile, high-style role of Blair Waldorf, a scheming good girl who shares the luxe life with other fabulous Upper East Side prep-school teens. It's the sort of role, on the sort of show, that could make a household name out of Meester, along with her co-stars Penn Badgley (who plays Dan), Chace Crawford (Nate), Ed Westwick (Chuck) and Taylor Momsen (Jenny).

And don't forget Blake Lively, who plays Serena van der Woodsen, a notorious party girl now haunted by regrets. Serena is Blair's best friend and worst rival.

The series, which premieres Wednesday, is based on the popular 'Gossip Girl' young-adult novels. But its transition to TV is thanks to Josh Schwartz and Stephanie Savage, the creative team behind 'The O.C.'

Once again, they face a daunting challenge, which Schwartz, by phone from L.A., put this way: 'How do you take a world that feels very exclusive and very rarefied, and make it universal? How do you make the viewer care about characters who seemingly have it all?'

If 'The O.C.' is any clue: By playing the exotic against the everyday; by striking a shrewd balance between what viewers have and what they pine for.

'I think the show will be relatable to lots of girls and even grown women,' says Meester confidently. 'And a guilty pleasure for guys!'

Could anything be more in synch with the zeitgeist? From her first 'Gossip Girl' novel five years ago, author Cecily von Ziegesar presumed a Facebook/MySpace/blogospheric culture that, only now, is coming true.

Here is a TV show whose narrator, like the novels', is an unidentified text-messaging guru. Gossip Girl, whoever she is, has her finger on the pulse of this trust-fund set - the loves, ambitions, feuds and wretched excess. As voiced by Kristen Bell ('Veronica Mars'), Gossip Girl's blogging keeps everybody in the know, while keeping everything stirred up.

Last March, Meester and her cast-mates shot the pilot, which will air as the series premiere, then waited to find out if they would be on the CW's fall schedule.

A couple of months after that, she's back, to film episode two ... and beyond.

'There's butterflies, definitely,' Meester says. 'But it's a good kind of nervous energy, because everybody's really starting to get to know each other and starting something new that we really hope works out.'