Also, Serena runs into Charlie in Los Angeles still unaware about her real identity, Ivy Dickens, who has moved to California with her boyfriend, Max.
Blair tries to conceal the news of her recent pregnancy from Louis as the arrival of her future sister-in-law Beatrice (guest star Roxane Mesquida) nears.
Dan is about to be announced as author of "Inside" so he gives a copy of the book to Blair, Serena, Nate, Chuck and Rufus hoping they will be supportive at his upcoming book party.
In the book, Dan described Serena as the "old Serena": drinking, dating teachers, being shallow, partying, reckless, and having random sex.
Hugo Becker also reprises his role as Blair's love interest, Prince Louis Grimaldi of Monaco. While working as a production assistant in Hollywood, Serena makes a mistake while trying to impress her new boss (guest star Michael Michele).