The Wrong Goodbye (Gossip Girl)

After discovering that Charlie has not been taking her medication, Serena and Vanessa reluctantly team up to find her. Chuck, Nate, Vanessa, and Serena soon encircle Dan, exclaiming that they need something from him. Chuck asks him where Blair is while Serena and Vanessa ask for Charlie's whereabouts. One of Blair's old friends reveals that Blair left the party. While accompanying Chuck to their apartment to look for Blair, Nate confesses that he told Raina (Tika Sumpter) everything behind her mother's death. Chuck reprimands Nate until Raina interrupts them to apologize. Blair is held hostage by Russell in Chuck's hotel. Pretending to escape, she calls Chuck on her phone, revealing her location. Russell explains his reason for kidnapping Blair: to burn down the hotel with her in it. A drunk Charlie is seen dancing wildly until Dan confronts her, but she escapes. Serena greets Headmistress Queller (Jan Maxwell), who expresses her concern with Serena's choice of staying in New York City, having hoped that Serena would find her place outside of the Upper East Side. Georgina offers her aid in their scheme but Dan, Vanessa, and Serena reject her help, going their separate ways to find Charlie.

At Chuck's hotel, Chuck saves Blair while Raina stops her father. With the police arriving, Chuck offers Blair a limo ride, and a homesick Raina breaks up with Nate, intending to return to Chicago. Chuck proposes avoiding the Constance party by going to a bar mitzvah in a similar fashion to Death Takes a Holiday, which Blair accepts. Chuck and Blair have sex while Prince Louis (Hugo Becker) waits for Blair at Constance. While looking for Charlie at the loft, Vanessa spots Dan's novel and reads it. Dan calls her and is upset that she has been reading the novel, which she suggests that he publish despite the possible backlash. Realizing that he no longer cares about writing, Vanessa steals the novel after Dan angrily dismisses her. Serena stops Charlie from jumping off a window and Charlie expresses her envy towards Serena, aspiring to be like her until Serena admits her personal flaws to Charlie, who comforts her. Dan and Nate find Charlie and Serena and return to the party. Charlie makes a suspicious call to her mother and piques Georgina's interest, who gives her her number. Blair finds herself in a dilemma as her feelings for Chuck have resurfaced, arriving at the party to inform Louis of her decision but Chuck interrupts her, informing him that he has their blessing. Blair confronts Chuck for making a decision for her, but the two eventually settle their issues, and he lets her go.

Three weeks later, Blair travels to Monaco to spend the summer with Louis while Serena goes to Montecito, Charlie departs for Miami, Chuck and Nate decide to travel together, and Lily (Kelly Rutherford) tells the family that her house arrest will end by autumn. Dan decides to spend summer in The Hamptons with Eric (Connor Paolo) and tells Rufus (Matthew Settle) that he has moved on from writing. Vanessa has Dan's novel published and leaves for Spain. While in California, Serena runs into a man who has been trying to convert one of her favorite novels into a movie, but finds herself being given a job instead. In Miami, Carol (Sheila Kelley) pays Charlie, who is actually a con artist named Ivy that was hired to gain access to her daughter's trust fund. Ivy's bag shows that she has stolen money from Carol and plans on returning to New York. A later scene shows a positive pregnancy test in a trash can at Blair's bathroom being thrown out by Dorota (Zuzanna Szadkowski).

"The Wrong Goodbye" is the second part of the two-part season finale. Gossip Girl executive producer, Joshua Safran notes that the most important returning character of the show was Georgina Sparks and discussed working on a two-part season finale for the first time on the show.

"I think that it's really fun. It's always fun to have Georgina around. She justs stirs the pot in a major way. She sort of threads through all the major stories [...] sort of like a witness until she injects herself. And of course, returning to Constance, you can't return without Georgina.[...] So a lot of things are in play and a lot of things are happening [...], since we've never done a two-parter before, we wanted to load the gun with as many bullets as possible."^[3]

Following her role in Green Lantern, news surfaced of Blake Lively leaving the show to further her acting career in Hollywood. IOL notes "Despite all talk of career trajectories and fanbase, Blake insists her choices are made through far simpler criteria and when asked about playing in a comic-book film says: 'It’s not really a suitable question because the decisions I make on parts come from a more emotional place. It has to be a character I connect with or someone I can have empathy with.'"^[4] New York Magazine and various media periodicals have also noted the possibility of Lively leaving the show.^[5][6][7] Serena and Georgina's dresses were designed by Jenny Packham and Marchesa, respectively.^[8] Blair wore an Alexis Mabille dress while Chuck wore a Ralph Lauren suit.^[9]

Oscar-nominated director David O. Russell made a cameo appearance in the show.^[10][11] Actor Ethan Peck reportedly landed a role in the show.^[12] Both stars were seen filming with Blake Lively in California. Peck made his debut in the season finale together with Russell.^[13][14] Tony Award-winning actress Jan Maxwell reprised her role as Headmistress Queller for the season finale. Hugo Becker remained ambiguous on whether he would be joining the series as a recurring or regular cast member during an interview with Zap2it, stating "the answer is in the finale." and hinted the possibility of a recurring role.^[15] Cecily von Ziegesar makes a cameo appearance during the finale and filmed her scenes with Lively.^[16]

The Airborne Toxic Event made a special appearance as the band for the Constance Billard Alumni party, playing the song "Changing" from their sophomore album, All at Once. The band announced that they would performing in the finale on their website.^[17]