Sneak Peek: A Gossip Girl Wedding!

Leighton Meester and Blake Lively (as Blair Waldorf and Serena van der Woodsen, respectively) trade their plaid uniforms for bright floral dresses to attend the Upper East Side's wedding of the year: the Bass-van der Woodsen nuptials.

Chace Crawford (who plays Nate Archibald) and Penn Badgley (Dan Humphrey) kick back between takes of the

wedding ceremony. But here's something to gossip about: Where did Chace let his other shoe fall?

No wedding day jitters here! The new onscreen family is the picture of

Upper East Side elegance as they smile for the camera.

Jessica Szhor – as Brooklynite Vanessa Abrams – glams up

in a frilly orange frock and high heels as she enters the wedding reception.

Poor Blair, looks like Nate is serious about his new love interest!

Wonder who's going to throw the first punch? In a heated scene, Chuck Bass

(played by Ed Westwick) confronts his former BFF Nate as a concerned Vanessa looks on.