Serena invites Aaron to a charity event, but soon uncovers a secret Aaron has been keeping from her. Thinking it will help her get into Yale, Blair agrees to babysit the 15-year-old daughter of a Yale donor, but her plan quickly backfires. Meanwhile, Jenny and Agnes plan a fashion show.

Devastated by the turn her life has taken, Blair opts for a wild lifestyle instead of her perfect Waldorf life, causing Chuck and Serena to become concerned. Vanessa tries to convince Nate that he needs to move on after his mother's family, the Vanderbilts, abandoned him and his mother. Trying to be honest with each other, Lily and Rufus both put together their lists of past relationships.