Gossip Girl (2007): Season 4, Episode 20

4 - 20: The Princesses and the Frog

A jealous Serena attempts to use information from Blair's past to threaten her newfound happiness with Prince Louis whose parents disapprove of Blair. After discovering a shocking secret, Nate is torn between his relationship with Raina and his friendship with Chuck. A questionable friendship arises between Charlie and Vanessa.