Episode Overview
Blair is caught off-guard – and not in a good way – by a surprise guest at her birthday party. Having had enough of Chuck and Blair's games, Serena and Nate decide to plan an intervention.
Guest Stars
Jayne Atkinson
Dean Reuther
Sam Page
Colin Forrester
Rachel Zoe
Rachel Zoe
Joe Zee
Joe Zee
Katie Cassidy
Juliet Sharp
David Call
Ben Donovan
Connor Paolo
Eric van der Woodsen
Amanda Setton
Penelope Shafai
Zuzanna Szadkowski
Dorota Kishlovsky
Alice Callahan
Jessica Leitenberg