Leighton Marissa Claire Meester (born April 9, 1986) is an American actress and aspiring Singer-Songwriter, best known for her role as Blair Waldorf in the TV show Gossip Girl.^[1] Her first acting role on a television program was on NBC's legal drama Law & Order in 1999.^[2] Other series in which Meester has appeared include Surface, Entourage, CSI: Miami,^[3] 8 Simple Rules, 24,^[4] 7th Heaven,^[5] and House.^[6]