Leighton Marissa Meester (born April 9, 1986) is an American actress, singer, songwriter, and fashion model best known for her role as Blair Waldorf in the television series Gossip Girl. After her television debut in 1999 playing Alyssa Turner in Law & Order, Meester appeared as a guest in two more series before landing her big role in the movie Hangman's Curse, based on the best-selling book by Frank Peretti. Meester also appeared in Tarzan, which ran for only eight episodes. Meester started to land guest roles in other series such as Crossing Jordan, 7th Heaven, Veronica Mars, 24, and Entourage.
In 2005, Meester began a regular role in the series Surface as Savannah Bennet. Meester appeared in two more 2006 movies, Flourish and Inside. She also guest appeared in Numb3rs and in two episodes of House M.D. as Ali, a young girl who has a crush on House. After guest roles on CSI: Miami, Shark, and playing the female lead in the horror film Drive-Thru, Meester was cast in CW's Gossip Girl as Blair Waldorf. The show is based on the book series by Cecily von Ziegesar about the lives of New York's privileged Upper East Side young adults. Her performance has been met with critical acclaim. In 2007, Meester appeared on the television film The Haunting of Sorority Row, and played a part in the ensemble comedy/drama Remember the Daze. She also appeared in the horror/thriller film Killer Movie in 2008.
Meester had a small role in the 2010 comedy Date Night and a cameo on Going The Distance. She was cast in Screen Gems's upcoming dramas Country Strong and The Roommate. She will star in The Uncatchable Cowgirl Bandits of Nottingham, Texas alongside Amber Heard; in the indie dramatic comedy The Oranges opposite Hugh Laurie; and will star next to Selena Gomez and Katie Cassidy in the young femme comedy Monte Carlo, loosely based on Jules Bass's young-adult book Headhunters.