Nate reconnects unexpectedly with Diana, the woman from LA, who offers him an exciting job opportunity. Meanwhile, Serena asks her cousin Charlie to come back to New York with her. Dan seeks out Chuck's help to stop the publication of his book, but discovers it is Chuck who needs help. Blair's future sister-in-law, Beatrice, arrives from Monaco, but her motives with Blair may be more than just to get acquainted. (IMBD)