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.
| Creator | Stephanie Savage |
|---|---|
| Actor | Blake Lively, Leighton Meester, Penn Badgley |
| Country | United States of America |
| Production | Warner Bros. Television |