"Gossip Girl" is a popular TV series and book series that revolves around the titular character, Gossip Girl, an anonymous blogger who exposes the secrets and scandals of the wealthy teenagers attending an elite private school in New York City.
The identity of Gossip Girl is a mystery for most of the series and is eventually revealed to be Dan Humphrey, one of the main characters.
If you're thinking of a different show, please provide more information about the show's title or plot, and I'll be happy to help!