Duration: 42m

TV-14 7.4 Drama / Mystery / Romance

Gossip Girl S4E19

Serena and Charlie go undercover to find out why Dan and Blair are so close.

Release Date: April 25, 2011 (USA)

Creator: Stephanie Savage & Josh Schwartz

Cast: Blake Lively, Leighton Meester, Penn Badgley, Chace Crawford, Ed Westwick, Kelly Rutherford, Matthew Settle, Taylor Momsen, Jessica Szohr