Serena throws Jenny a sixteenth birthday party, but things spin out of control when Poppy Lifton turns the party into the social event of the season. Vanessa agrees to help Chuck in a plan concerning Blair and Nate. Meanwhile, Rufus searches for a way to cover Dan's tuition when he learns he will not receive financial aid to go to Yale.

Serena returns from her trip to Spain with Poppy and Gabriel. Blair makes a secret deal with Nate's grandfather. Dan takes a job to earn money for college.

Georgina returns to the Upper East Side but it's not the same Georgina we all knew, she's changed. Chuck and Nate's relationship is at a crossroads because of their mutual interest in Blair. Serena's relationship with Gabriel gets more complicated.

Blair puts pressure on Georgina to making amends for her past bad behavior by helping her in an evil plan. The rivalry between Nate and Chuck over Blair reaches a boiling point. Lily makes a secret plan to help Rufus with Dan's college tuition.