The O.C. creator Josh Schwartz made the revelation while appearing as the first guest on Rachel Bilson and Melinda Clarke's rewatch podcast
Benjamin McKenzie and Mischa Barton
Credit: Albert L. Ortega/WireImage

The O.C. could have looked very different if other casting plans had gone through, according to series creator Josh Schwartz.

Earlier this week, former The O.C. stars Rachel Bilson and Melinda Clarke launched their brand new rewatch podcast, Welcome to The OC, Bitches!. Fittingly, they welcomed Schwartz, 44, as the first guest on the series' inaugural episode.

During their conversation, Schwartz spoke about the teen drama's casting process, as he revealed that series stars Ben McKenzie and Mischa Barton — who played Ryan Atwood and Marissa Cooper, respectively — weren't the top choices for their roles.

Speaking about McKenzie's role of Ryan, Schwartz revealed that Garrett Hedlund and D.J. Cotrona were originally up for the part — and that McKenzie, 42, was "different than what we imagined" for the role.

"We had looked at a lot of people and he had read for a show, a comedy for the then-UPN and didn't get it and one of the executives at Warner Bros. said, 'We just saw this kid, he's really good, you should see him,' " Schwartz recalled. "I remember walking up to the casting office and Ben was just outside, I believe he was smoking ... he gave us not a big warm hello. I was like, this guy's really interesting. It's a different way than we envisioned it. He was so good and felt so soulful."

As for the part of Marissa? Schwartz revealed that the role almost went to Olivia Wilde, who would later have a role in the second season of The O.C.

"Olivia had just moved out to L.A., it was one of her first auditions and was super compelling," Schwartz said, before noting that Barton's younger age, "just had a bit more of that tragic air to her."

Benjamin McKenzie and Mischa Barton
Credit: Bruce Glikas/WireImage; Jared Siskin/Patrick McMullan via Getty Images

Continuing his candid revelations, Schwartz shared that Adam Brody "wanted to read for Ryan" before he was later cast as Seth Cohen.

Detailing that the role of Seth was "way nerdier" in the original script, Schwartz said, "The network had the note that he's a little too nerdy. We need this guy to be a co-romantic lead of the show. But Adam has such natural swagger, is cool, good looking and funny. Him playing against that was charming,"

The OC
Credit: Warner Bros Tv/Kobal/Shutterstock

"When he first came in and read, I think it was the middle of pilot season, and he didn't really know any of the words to the scene, I was kinda like, 'How dare you come in here and not know the words?' We kept seeing other people after that," he continued.

But those working behind-the-scenes on The O.C. decided to give Brody, 41, another chance, eventually casting him in the role that Schwartz said made everyone fall "in love with him."

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Meanwhile, Bilson, 39, shared that she initially wanted to audition for Marissa.

"I had read the material before I got the audition for Summer and I was like, 'I want to read for that part, I loved it,' " she explained. "I got called in for Summer and was like, man, I really wanted Marissa and here we are."

Melinda Clarke; Rachel Bilson
Credit: Joe Scarnici/Getty Images; Gabriel Olsen/Getty Images

Similarly, Clarke, 52, said that when she auditioned, she read for the part of Kirsten, which eventually went to Kelly Rowan.

"Then you brought me back for Julie dialogue," Clarke said to Schwartz. "I was under contract for another show, I think it was Babylon 5, and they wouldn't let me out. We begged for myself to get let out of that other contract and I went to work the next day."

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Welcome to the OC, Bitches! — a nod to one of the teen drama's most iconic lines — will feature "former cast members, writers, musicians, and many people that made The O.C. the cultural phenomenon that it is today" as Bilson and Clarke recap every episode of the show.

"Grab your bikinis, your Juicy jumpsuits and your flip phones because every Tuesday, we're going back to the early 2000s," Bilson says in the podcast's teaser.

New episodes of Welcome to the OC, Bitches! premiere every Tuesday.