Barton first appeared on television in 1996, as young Lily Montgomery in the soap opera All My Children, and in a modern re-make of Bonnie and Clyde. She guest-starred in eight episodes of the television series Once and Again as Jessie Sammler's (Evan Rachel Wood's) girlfriend, Katie Singer. Other television appearances include an episode of the FOX series Fastlane, James Blunt's music video "Goodbye My Lover",and Enrique Iglesias' music video "Addicted".In August 2003, FOX premiered the television series The O.C., about affluent teenagers with stormy personal lives who reside in scenic Orange County, California. The show became an overnight success because of the large fan base, and it put Barton on the map as Marissa Cooper, until her departure from the show in the third-season finale in May 2006. The O.C. dropped in ratings dramatically during its third and fourth seasons, and ended in early 2007.
