Mischa Anne Marsden Barton (born 24 January 1986) is a British-American fashion model, film, television, and stage actress. She began her acting career on the stage, appearing in Tony Kushner's Slavs! and took the lead in James Lapine's Twelve Dreams at New York's Lincoln Center. She made her screen debut, making a guest appearance on the American soap opera All My Children (1996).
She then voiced a character on KaBlam! (1996-1997), an animated television series on Nickelodeon. Her first major film role was as the protagonist of Lawn Dogs (1997), an acclaimed drama co-starring Sam Rockwell. In 1997, she also landed a Calvin Klein campaign. She continued acting, appearing in major box office pictures such as the romantic comedy, Notting Hill (1999) and M. Night Shyamalan's psychological thriller, The Sixth Sense (1999).
She later appeared in the independent drama, Lost and Delirious (2001) and played Evan Rachel Wood's girlfriend during a guest-arc on ABC's Once and Again (2001-2002). She is best known for her role as Marissa Cooper in the Fox television series The O.C. (2003-2006), for which she received two Teen Choice Awards and a Prism Award nomination. Entertainment Weekly named her the "It Girl" of 2003.
She has since appeared in the comedy remake St Trinian's (2007) and the Richard Attenborough-directed drama Closing the Ring (2007). In 2008, the neo noir comedy, Assassination of a High School President premiered at the Sundance Film Festival. This was followed by the Roland Joffé drama, You and I which premiered at the Cannes Film Festival later that year.
She returned to television, starring in the short-lived Ashton Kutcher-produced CW series, The Beautiful Life: TBL (2009) and made a guest-appearance in Law & Order: Special Victims Unit (2010). In 2010, she was announced as the face of Philipp Plein couture. Her upcoming releases include Bhopal: Prayer for Rain, a drama about the Bhopal disaster alongside Martin Sheen.
Mischa Barton was born in Hammersmith, West London, to an Irish mother, Nuala (née Quinn), a photographer, and an English father, Paul Marsden Barton, a foreign exchange broker from Manchester. She has two sisters, younger Hania and elder Zoe, a barrister in London.
Her father's work took the family to New York City when Barton was six, and in 2006, ten days after her twentieth birthday, she became a naturalised citizen of the United States. She has retained her British citizenship and, in reference to her English roots, states "I actually feel more comfortable in England a lot of the time", yet stresses that, "I like people to discern that I'm an English-Irish girl who grew up in New York."