Gossip Girl (season 6)

The summer is over and Serena has gone missing. After a brief encounter abroad, Blair and Chuck make a promise to each other about their relationship, which leaves them once again apart. Dan, with some help from an unlikely ally, Georgina, is writing a scathing tell-all book that can only mean trouble. As the sole head of The Spectator, Nate is making his own decisions and is ready to go up against Gossip Girl. As word spreads that Serena is missing, the gang bands together to find her and are shocked by what they find.

Trying to prove herself in adult society, Serena hosts the Central Park Conservancy's big gala, of which she is now the newest board member, and she and Nate both learn something shocking about their significant others. Blair prepares to debut her new fashion line, but a rival from her past holds the key to her future. With the help of Georgina, Dan lands some meetings with publishers, but he must decide if he is willing to sacrifice his integrity in order to get his work published. Meanwhile, Chuck tries to persuade Amira to help him look into his father's past, even if it means jeopardizing Lily and Bart's relationship.

Feeling the pressure to make her first Waldorf Designs fashion show a success, Blair must rely on help from an unlikely source, but some unexpected scheming causes a scandal on the runway. Serena discovers that befriending Steven's daughter Sage is trickier than she thought, especially when she is forced to put her issues with Blair aside to make Sage happy. Nate publishes Dan's first serialized article causing a stir and producing a serious threat. Meanwhile, Chuck begins to look into the clue that Amira left behind, which may help uncover what Bart is hiding.

Chuck's continued investigation into his father's dealings leads him to an unlikely event with Manhattan's elite, where he hopes to find the one person who can tell him the truth about Bart. Serena and Steven decide to reveal their romantic histories so they are not surprised about anything, but neither was prepared for what they uncovered. With The Spectator in jeopardy after Dan decided to publish elsewhere, Nate must make a difficult decision to keep it in business. Meanwhile, Georgina pushes Dan to choose a worthy person to date to boost his image, but he finds himself drawn in a different direction. Elsewhere, Ivy tries to persuade Rufus to go through and unpack a group of boxes with all of his stuff from the apartment that Lily had sent over to the loft after he moved out.

After Eleanor gives Blair an ultimatum, Blair is even more determined to remedy Waldorf Designs' problems by making a splash with a dress at the upcoming cotillion, but a shocking revelation at the ball affects everyone. Serena becomes worried about Steven's attitude toward her, but after some investigating she discovers the surprising reason why. Sage learns that her father plans to propose marriage to Serena and plots an all-out attack to destroy the engagement once and for all despite the risk of endangering her relationship with Nate. Chuck finds an unlikely ally in Ivy as he tries to drive a wedge between Bart and Lily's relationship to help expose his father's secret. Meanwhile, Dan publishes another article, but the effect is just the opposite of what he was hoping for as Georgina continues to pressure him to publish more. Elsewhere, Rufus learns about Ivy's inheritance as she continues to help him rebuild his life.

Blair gets ready for her mother's imminent arrival, but is unprepared for the set of demands her mother puts upon her. Serena volunteers to help Dan find a new place to live, but their time together brings up unexpected emotions. With Ivy's help, Chuck discovers there is evidence incriminating his father in illegal activities and enlists the help of Nate to retrieve it. Meanwhile, Rufus and Ivy are excited about their art gallery opening until they find an empty RSVP list and must scramble to find another way to make the event a success.

Serena and Dan realize that they need to make amends with the people they have wronged to rebuild their shattered lives. Blair has one last chance to prove to her mother her worth as a fashion designer and with Serena's help, comes up with a plan to make her line the "it" look for Sage and her friends. Chuck is close to getting the evidence he needs against his father, until one of his closest allies reveals his plan to Bart.

Serena and Dan decide to throw their first Thanksgiving dinner together, inviting only their closest friends, but everyone seems to have their own agenda for attending. Serena has a run-in and invites both Steven and Sage to the dinner, while Lily and Bart also crash the event which fuels the tension between everyone. Feeling defeated by his father, Chuck begins a downward spiral, leaving Blair to find a solution to his problems. Meanwhile, Dan has written his latest exposé, but he must make a tough decision whether to publish it, knowing it could destroy a close friendship with Serena and everyone else that he knows.

After a run-in with an increasingly paranoid Bart, Blair grows alarmingly concerned for Chuck's safety. Feeling confident that his father will never hurt him, Chuck makes a deal that could change his life. Blair devises a plan with the help of Serena, Georgina, Sage and Ivy to get what they need out of Bart. Meanwhile, Nate's financial dilemma lands him in a place that he never thought he would be; jail. In the end, Chuck is escorted by Bart's security to the roof of a building, minutes later Bart joins him. Blair, alarmed at not being able to locate Chuck, asks around for him and races up to the roof as well. A fight ensues between Chuck and Bart and Blair arrives just in time to see Bart hanging off the side of the building. Chuck refuses to help him up for fear that he would harm his friends or himself. The episode ends with Bart falling and Blair and Chuck running off.

Serena decides to come back to New York and confront Dan about the "Serena Chapter". Chuck proposes to Blair when he is implicated in the death of Bart. Georgina joins forces with Jack Bass in one last scheme to help Chuck and Blair. Nate and Sage try to find the identity of Gossip Girl with the information that they have. William van der Woodsen returns to comfort Lily and rejects Ivy who finally realizes that William used her just to win Lily back. Dorota, Eleanor Waldorf and Cyrus Rose also become involved in planning Chuck and Blair's improvised wedding. Various characters from previous seasons make cameos, including Vanessa, Juliet, Agnes and Lola. Kristen Bell has a cameo as herself alongside Rachel Bilson. Dan is revealed to be Gossip Girl.

Five years later: The group gathers for Dan and Serena's wedding. Eric and Jenny are both in attendance as is Eleanor and Cyrus Rose who is delivering the vows. Nate has become successful with The Spectator and will likely run for Mayor of New York City. Chuck and Blair are still married and have a four-year-old son named Henry Bass. Ivy has written a best-selling autobiography titled Ivy League which has been adapted into a major Hollywood feature film with her as the screenwriter and starring Olivia Burke and Lola Rhodes as the Serena and Ivy/Charlie characters. Georgina and Jack have gotten together, Lily and William are finally back together, and Rufus is with Lisa Loeb. In the final shot, a new generation of wealthy Upper East Siders are seen at Constance as a new lonely boy walks past his classmates, denoting the beginning of a brand-new Gossip Girl.