Serena's world is thrown into a tail spin when her former cohort, Georgina Sparks, returns to the Upper East Side in order to start trouble and reveal Serena's past in the process. When Dan notices Serena seems to be preoccupied, he assumes that it's due to her future brother-in-law Chuck. Meanwhile, Nate finds a new romance with Vanessa; Jenny meets a new guy, Asher Hornsby, who may be her door to permanent popularity; and Blair launches a plan to take down her rival, Nelly Yuki.