Serena enlists Charlie to go undercover Gossip Girl-style to determine why Dan and Blair are spending so much time together, and what role an unexpected visitor is playing in their lives. With Nate’s help, Raina decides to go on a search for her long-lost mother. Chuck’s hopes about his legacy are dashed with the reveal of devastating information from the past.
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 .