Gossip Girl premieres tonight — are you excited? Before you tune in, get a sneak peek of Blake Lively, Leighton Meester, and the rest of their cohorts in their stylish Gossip Girl gear. So far, we spy Blair Waldorf in a sunny yellow outfit by Stella McCartney, Serena van der Woodsen sporting Rag & Bone, and newcomer Roxane Mesquida, set to play the role of Prince Louis's sister, on set wearing Valentino florals. Want to see what else they have in store for the new season? Click the slideshow to see the girls working their Upper East Side style.