It was 2003 when Entertainment Weekly crowned British-American actress Mischa Barton their “It Girl” of the year.

Barton, whose freshly minted leading role on The O.C. had catapulted her into mainstream fame, was not yet 18 when she received the sparkly accolade. She was a teenager; one who was heralded as the ultimate socialite some four years before she could legally do any of the things socialites are notorious for.

While the character of Marissa Cooper was the same age as her fictional best friends on the smash teen drama, in reality that wasn’t the case. Barton was years younger than each of her counterparts in the real world; Ben McKenzie, Adam Brody and Rachel Bilson were all in their twenties when worldwide fame knocked on the door. But for the show’s biggest star, the final years of teenagerdom would be played out in front of the prying eyes of the paparazzi media.

For a few years, it worked.

Barton was the epitome of what it means to be young, rich, white and shiny. She won awards for Breakout TV Star in 2003 and Best TV Actress in 2006 at the Teen Choice Awards. Even after departing The O.C., with 76 episodes under her belt, Barton went on to considerable success. She would lead 2007 British comedy film St Trinian’s to solid box office profits before, in 2008, delivering a “captivating” performance alongside Bruce Willis in Assassination of a High School President.

The Mamamia Out Loud team discuss the problematic nature of making teens icons. Post continues.

Barton’s pop-culture relevance was not lost on the London-born model, who told The Guardian:

I like to choose brands I feel comfortable repping. There’s a million offers and you have to pare it down. Even sometimes when I go to Fashion Week I have so many designers that I like and am friendly with, or have done favours for me in the past, that it gets a little overwhelming. John Galliano is great; Dior has been wonderful, giving me couture dresses from the runway and always inviting me out to Paris.

In the same year she would win InStyle‘s “icon of the year” award. The trophy was placed in Barton’s hands by Karl Lagerfeld, who commented: “So many girls want to look like Mischa Barton. She is a fashion role model for an entire generation.”

The quotes came around the same time that she told The Independent, “You can’t avoid the paparazzi they’re everywhere. It’s become a whole thing now… I just go out less and stay at my house.”

It was, ironically, also the time that Barton’s fashionable celebrity life began to fray at the seams.

An arrest over driving under the influence of alcohol and marijuana, without a licence, would be Barton’s first public indiscretion, the controversy around which would bleed well into 2009, when Barton was involuntarily held in a psychiatric hospital for two weeks. The admission, which is referred to as a 5150 hold in the U.S., is only employed when a person is deemed to be afflicted with a mental disorder, and considered a risk to themselves or others.

While Barton’s PR machinery played the incident down as a misunderstanding – the actress insisted she was simply held there because she disagreed with nursing staff after a wisdom tooth operation – the truth was far messier.

Years passed before Barton would tell People, “It was a full-on breakdown… I was under enormous pressure… I was just overworked and depressed.”

After her stint in a psychiatric hospital, the life of Mischa Barton pivoted to a more colourful and complicated place than perhaps the fashion heavyweights who once championed her thought possible. Rom-coms and glitzy teen films were swapped out for the genre an adult Barton became fixated upon: horror.

"I literally became obsessed with that genre. I can't tell you," she said. "... Suddenly I got really into all this automatic writing, paranormal shit; real stories of people who have been haunted. And in my own family, my father tends to be very sensitive to that stuff. I don’t know why; a switch flicked, and I really wanted to do these creepy movies."

Almost all of Barton's work since her intervention has been in indie psychological thriller and horror films; in 2018 she will star in Painkillers - a thriller that follows the life of a grieving surgeon, who finds solace only in the taste of human blood. Last year she appeared in The Toybox, a horror film about a cross-country road trip that is destroyed by an "otherworldly evil".

While she may no longer grace the covers of the magazines you mindlessly flick through at the hairdressers, the grittiness of Barton's life has, at times, penetrated the news cycle. In 2015 she sued her mother and former manager Nuala Barton for "fraudulent misrepresentation" - an allegation that Nuala labelled "heinous" and "false" and saw the pair become estranged.

Last year, neighbours filmed Barton in her own backyard when she began screaming about the end of the world. The video was shopped around and promptly shared with the world by TMZ. Police attending to the scene took Barton to hospital.

"I was informed by their staff that I had been given GHB. After an overnight stay, I am home and doing well," Barton told People the following week.

And now, today, you might see Mischa Barton's face on major news websites; she's being sued for $26,991 in damages after allegedly driving a removalist truck into a condo building. She denies ever being behind the wheel of the vehicle, despite video footage taken by onlookers at the scene suggesting otherwise.

Like the teen 'It girls' who came before her - Lindsay Lohan, Amanda Bynes, Britney Spears - Mischa Barton's life has shifted and morphed into the antithesis of who she was at 17.

Now 32, Barton no longer neatly fits the adult mould the world made for her when she was a teenager.

Eleven years after she first portrayed Marissa Cooper, Barton was asked whether she would take the role on The O.C. if she had her time again.

"Probably not," she told Metro.

“It’s tough. It’s really tough when you are young in this business. It’s just one of those things when you are growing under a microscope and changing and that evolution is human.

"That humanity aspect means flaws – which people don’t want to see.”

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