How Old Was Mischa Barton When The O.C. Started?

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2000s drama queen Mischa Barton made many red carpet appearances in 2016. In June of the same year, the then 30-year-old The O.C. actress attended the 2016 Stylight Awards in Berlin, where she served as a jury member.

Mischa Barton wears her blonde hair down at the 2016 Stylight AwardsMischa Barton wears her blonde hair down at the 2016 Stylight Awards held at Admiralspalast on June 28, 2016 in Berlin, Germany (Credit: AEDT / Frederic / Future Image / WENN)

Famous for her portrayal of Marissa Cooper on the hit television drama “The O.C.,” which aired from 2003 to 2007, Mischa Barton was 17 years old when the first episode of “The O.C.” aired on August 5, 2003.

She was the youngest of the main “teenage” characters in 2003 when the series began. The show ended on February 22, 2007, when Mischa Barton was 21 years old.

The O.C. actresses Mischa Barton and Rachel Bilson at the Teen Choice Awards 2003The O.C. actresses Mischa Barton and Rachel Bilson at the Teen Choice Awards 2003 held on August 2, 2003, at the Universal Amphitheatre, Universal City, California (Credit: DFree / Shutterstock)

Her last appearance was in The Graduates, the twenty-fifth episode in the third season that aired on May 18, 2006, when she was 20 years old.

In a memorable scene from “The O.C.,” the characters poke fun at Seth (played by Adam Brody) for vomiting “like that girl from ‘The Sixth Sense.'”

It’s a playful nod to Mischa Barton, who portrayed the iconic character of the haunted young girl in the 1999 film.

The main cast of "The O.C." includes Benjamin McKenzie as Ryan Atwood, Mischa Barton as Marissa Cooper, Adam Brody as Seth Cohen, and Rachel Bilson as Summer RobertsThe main cast of “The O.C.” includes Benjamin McKenzie as Ryan Atwood, Mischa Barton as Marissa Cooper, Adam Brody as Seth Cohen, and Rachel Bilson as Summer Roberts (Credit: Featureflash Photo Agency / Shutterstock)

When the producers were casting for the role of Marissa Cooper, writer Josh Schwartz described her as “the most beautiful girl you had ever seen.”

Ultimately, they chose Barton for her unique and awkward beauty, which set her apart from the usual California blondes.

Olivia Wilde was also a finalist for the role of Marissa. Still, the writers felt that she was too strong for the emotionally unstable character, so they created the role of Alex Kelly for her instead.

Mischa Barton was 17 years old when the first episode of "The O.C." aired on August 5, 2003Mischa Barton was 17 years old when the first episode of “The O.C.” aired on August 5, 2003 (Credit: Warner Bros. Domestic Television Distribution)

Peter Gallagher and Mischa Barton were the first two actors to sign on to the show, but the producers had trouble finding the right actor for the role of Ryan.

Benjamin McKenzie was eventually cast at the last minute, rounding out the talented ensemble that would make “The O.C.” a beloved TV classic.

Mischa Barton wears a sheer beaded Blumarine dress to the 2016 Stylight AwardsMischa Barton wears a sheer beaded Blumarine dress to the 2016 Stylight Awards (Credit: AEDT / Frederic / Future Image / WENN)

At the 2016 Stylight Awards, she exuded glamour in a black semi-sheer dress, which featured long sleeves and beaded fringe, from Blumarine’s Fall 2016 collection.

The British-American actress layered the daring — but classy — frock over a red mini dress.

Mischa added a belt to the look to accentuate her tiny waist. She then teetered on a pair of strappy heels, which further elongated her statuesque frame.

Mischa Barton wears a beaded Blumarine dress cinched in with a beltMischa Barton wears a beaded Blumarine dress cinched in with a belt (Credit: AEDT / Frederic / Future Image / WENN)

The former “Dancing with the Stars” contestant kept everything else simple. She skipped the jewelry and rounded out the look with subtle smoky eye makeup and pink lipstick.

Mischa Barton shows off her figure in a beaded fringe Blumarine dressMischa Barton shows off her figure in a beaded fringe Blumarine dress (Credit: AEDT / Frederic / Future Image / WENN)

Mischa’s strappy sandals completed her edgy and elegant look.

Mischa Barton's feet in strappy black-and-gold sandalsMischa Barton’s feet in strappy black-and-gold sandals (Credit: AEDT / Frederic / Future Image / WENN)

They feature adjustable ankle straps and front straps in black suede material. They also have glittery asymmetric vamp straps and about four-inch gold heels.

Mischa Barton's feet in strappy black-and-gold sandalsMischa Barton’s feet in strappy black-and-gold sandals (Credit: AEDT / Frederic / Future Image / WENN)