Adam Brody Was 'Not Shy' About His Unhappiness on Set of 'The O.C.,' Costar Ben McKenzie Says: 'It Was a Challenge'

Adam Brody made it clear he was unhappy about being on set of The O.C. back in the day, according to a new book called Welcome to the OC: The Oral History, written by Rolling Stone TV critic Alan Sepinwall and The O.C. creator Josh Schwartz and executive producer Stephanie Savage.

Ben McKenzie, who played Ryan Atwood on the drama series, said Brody, who played Seth Cohen, was "not shy" about how he didn't want to be there. “[It was] a challenge, and frustrating," McKenzie said of the situation.

Meanwhile, Rachel Bilson, who played Summer Roberts and dated Brody in real life, said she knew the Gilmore Girls alum before appearing on The O.C., recalling how she thought he was "cute and funny" but also "kind of a d---."

There were even moments when Bilson wanted to tell Brody to "sack it up."

"How do you balance that? Because you want to be supportive of the person you're with. But also I'm a firm believer in always being grateful, and gratitude comes first," she recalled. "And I think there were probably times where that went by the wayside. You grow up, you look back, and you can realize when you're young, you might behave in certain ways you wish you hadn't."

Brody admitted he got "bored" of the show by Season 3, but he was still professional on set.

"I was polite to everyone. I liked the directors, and the crew and I got on really well and I didn't keep people waiting. I would never scream or yell at anyone, or say anything f-------- mean. But I think I very much let my distaste for the later episodes be known. I didn't mask that at all, and I'm sure I openly mocked it a bit. So I'm not proud of that," he stated.

"I started to be creatively less interested. I blame myself for a lack of professionalism, and a disrespect to the work. In terms of engagement as a whole, I'll just say that they're different shows, Season 1 and [the later seasons]," Brody continued. "Had the quality been the quality of Season 1, I'm sure I would have been a lot more engaged ... I think the quality of it and my engagement went hand in hand."

Schwartz also noticed how Brody became less engaged over time, which is why they let him smoke weed.

"Brody just changed his delivery, his investment in it. His style shifted to such a degree that we felt like we needed to account for it creatively. That's where 'Kaitlin gets Seth hooked on pot' took root," he claimed. "We were like, 'Well, how do we explain his lethargy on-screen? And at least if we can write that he's stoned, then we're not trying to write around it.'"

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