Leah Dolan, CNN

Before Blair Waldorf wore Oscar de la Renta to her high school prom, Marissa Cooper — the sun-kissed It Girl of “The O.C.,” which turns 20 on August 5 — was wearing Chanel to second period. Cooper, played by Mischa Barton, defined aspirational fashion for Millennial girls everywhere when she arrived on her high school campus, seemingly sporting a different Chanel purse each day. Only, none of them were real.

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The O.C was the original rich-kid teen drama, centered on the wealthy community of Newport Beach, Orange County. The stakes were high (Cooper eventually dies in her boyfriend Ryan Atwood’s arms after a dramatic car wreck, scored by Imogen Heap), the actors were sun-kissed and the trousers were almost exclusively capri-length.

Chanel was key to the symbolism of Cooper’s character: She’s affluent but not particularly opulent. There was a well-bred, classic elegance to her character that she was often trying to rebel against, usually through underage drinking or drugs. In turn, she habitually wore her high-end designer purses with a basic tank top or long sleeved shirt and flip flops. One would go as far to imagine she never picked out any of her bags, but that they were rather gifted to her by Julie Cooper, her overbearing and superficial mother.

"The O.C." turns 20 on August 5.

Some of Cooper’s most memorable looks featured a Chanel accessory. There was the large black quilted tote bag she stuffs her books and binders in when standing at her high school locker, the classic shoulder bag in burgundy patent leather, and even a brown leather flap bag. Some fans have counted that she debuted six different Chanel bags in the first season alone.

Building an on-screen wardrobe that exudes luxury is no small feat, particularly when you’re working on a burgeoning show. At least that was the experience of “The O.C.” costume designer Alexandra Welker. In an interview with Page Six in 2018, Welker said she resorted to buying fake Chanel bags to keep up appearances. “It was a challenge because everything (on the show) had to look super high-end,” she said. “There was absolutely no borrowing (from brands) involved either, because nobody had ever heard of us, so they were very leery of loaning anything.”

By the end of the first season, Chanel were sending real samples to Welker for the show.

Today, the genre of high school TV drama has undergone a sartorial shift. Thanks to the financial backing of streaming platforms and a new generation of costume designers such as Heidi Bivans — who outfitted the HBO Max show “Euphoria” — seeing on-screen teenagers in Coperni, Miu Miu and vintage Jean Paul Gaultier has become run-of-the-mill. (HBO Max is also owned by CNN’s parent company Warner Media Discovery).

Two decades ago, it was a different story for Welker. “People got really worked up over that Chanel book bag, they thought the idea of a teenager carrying one to school was obscene.”

The fakes Welker bought were from a single seller in Downtown LA. “Those Chanel bags that (Cooper) carried, those weren’t something I could have on my budget,” she reportedly said. “We used some really, really good knockoffs.”

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But by the time the team began to think about season two, the show had already gained momentum and a sizable fanbase. Each episode was pulling in an average of 9.7 million viewers, and the show was the highest rated new drama in 2003-2004. “By the season one finale, brands were falling all over themselves to lend to us,” Welker told Page Six. Even Chanel themselves loaded a handful of real samples for Cooper’s character. “And once we started using real Chanel, of course, I had to let those fakes fall by the wayside.”