The much-anticipated 100th episode will open with a musical dream sequence featuring Serena, Blair and all the men in their lives. Also, while Chuck wrestles with the reality that Blair is about to walk down the aisle with Prince Louis, the return of Georgina Sparks might make the royal affair a royal disaster.
Elenco: Blake Lively , Leighton Meester , Penn Badgley , Chace Crawford , Ed Westwick , Kelly Rutherford , Matthew Settle , Kaylee DeFer , Jessica Szohr , Kaylee De Fer , Kelly Rutherford , Kristen Bell , Matthew Settle , Michelle Trachtenberg , Taylor Momsen .