Nate and Serena decide to explore the boundaries of their friendship. Blair suspects that Chuck is having problems forgetting about the woman he saw at his father's grave. Jenny agrees to accompany Damien to a State Dinner, but she realizes that his plan is ruined by a memory of the school. Dan tries to overcome the confession of love for Vanessa, without any result. Rufus returns from a ski trip and tries his best to avoid Lily.
Rufus and Lily grow suspect of Jenny's relationship with Damien. Chuck (Ed Westwick) learns more about the woman who may or may not be his mother. Dan and Vanessa struggle through the awkwardness of dating other people.
Despite being grounded, Jenny continues to see Damien who tells Jenny that he wants to have sex with her. Lily thinks to tell the secret that she has supported conceal, but after a call, she changes of mind. Dan and Vanessa explore a new stage of their friendship. Chuck is forced to make an extremely difficult decision about his hotel. Meanwhile, Serena and Nate have a fight that is reminiscent of past events.
Chuck finds himself once again at odds with his uncle, Jack Bass. Eleanor puts Blair in charge of making sure her latest fashion show is a huge success with an important client. Rufus attempts to get Jenny back on track by volunteering to have her help with Eleanor's fashion show, but the opportunity takes a big turn for the worse when Jenny learns that Agnes will be one of the models.
Chuck and Blair are faced with the most difficult decision they have ever faced as a couple. Serena plans a surprise birthday party for Nate, but Jenny does her best to sabotage Serenas's efforts. Dan and Vanessa's new relationship hits a bump in the road.
Chuck offers to throw a wedding for a very pregnant Dorota who insists that she and Vanya have a traditional wedding before her parents arrive from Poland and find their daughter pregnant and without a husband. Dorota asks Blair and Chuck to be part of the ceremony and walk her down the aisle. Serena tells Nate she is having breakfast with the Humphreys when in reality she's secretly meeting up with Carter Baizen. Rufus discovers that Lily has been lying to him about her whereabouts.
When Lily's ex-husband, Dr. William van der Woodsen, shows up unexpectedly in Manhattan, Serena finally gets the reunion she has so desperately wanted with her father, but the circumstances turn out to be far from ideal. When Serena and Nate continue to have relationship issues, a scheming Jenny is more than happy to be a shoulder for Nate to lean on. Meanwhile, Dan finds out that he didn't get accepted into the Tisch writing program and Vanessa admits she may have been somewhat responsible.
Will's return to the Upper East Side continues to stir up problems for Serena, Lily and his long-standing rival, Rufus. Serena and Jenny's relationship is strained as a result of Jenny's deception. Blair spends time on the Columbia campus and realizes where she truly belongs. Dan learns that Vanessa has been keeping yet another secret from him.
When things get tense between Rufus and Will, Serena chooses to stand behind her father, while at the Rufus is made to feel like an outsider in his own family. Meanwhile, Jenny deliberately shares information with Will that may ultimately destroy Lily and Rufus' marriage. After many failed attempts, Chuck makes one last grand gesture to reconcile with Blair, hoping she will finally accept the fact that they are destined to be together.
Blair must decide whether to meet Chuck at the top of the Empire State Building or risk losing their future together. A Gossip Girl gossip bomb involving Dan explodes Serena and Nate's relationship. Dorota and Vanya welcome their baby. Jenny hits rock bottom. Georgina returns to the Upper East Side...and she has an agenda.
After having spent her Parisian summer alone (and in Serena's shadow), Blair hopes to change things when she meets a handsome young man who may be a real prince. But Serena has news that may only increase Blair's insecurity. Meanwhile, back in New York, Georgina and Dan's secret comes to light, and Nate meets a girl who seems refreshingly down to earth after a summer of Chuck Bass-rejects. And speaking of Chuck, he's still missing in action, which causes Lily to worry.
On her first day at Columbia, Blair attempts to gain membership into an ultra-exclusive social club, Hamilton House, but she's in for a few big surprises. Serena begins to suspect that Juliet is intentionally sabotaging Serena's life and that it may have something to do with Nate. Rufus is worried about Dan and decides to take matters into his own hands.
Nate suspects that Juliet is keeping a big secret from him and decides to confront her. Blair schemes to undermine Chuck's newfound happiness. Dan finds himself torn between his feelings for Serena and Vanessa.
An anonymous Gossip Girl blast starts a very damaging rumor about one of Columbia's new students, Serena. On her path to greatness, Blair decides to take a class with a powerful businesswoman, Martha, who is guest-lecturing at Columbia, but a mysterious fellow student thwarts her plans to secure the prized position as Martha's assistant.
Although Blair made it perfectly clear that Little J was no longer welcome in Manhattan after what happened with Chuck, Jenny is tempted by a once-in-a-lifetime opportunity to meet Tim Gunn, which could be a game changer for her future. Meanwhile, Serena discovers something about her new boyfriend, Colin, that may put an end to their relationship just as it was getting good.
Chuck and Blair decide it's in both their best interests to put the past behind them and end their vindictive games. Nate confronts Juliet after discovering a secret she has been keeping from everyone. Dan and Nate realize they both still have feelings for Serena.
Chuck hosts a "Saints and Sinners" masquerade party at the Empire Hotel. At the party, Dan and Nate don't know what to make of Serena's strange behavior and mixed messages. Blair sets her sights on becoming the new face of Anne Archibald's foundation for girls, but Anne is concerned that Blair's friendship with Chuck Bass may be problematic.
Chuck, Serena, Blair, Dan, Jenny and Eric find themselves faced with a crisis when a member of one of their families is hospitalized. Meanwhile, Nate attempts to help his parents, The Captain and Anne, put their complicated past behind them and reconcile.