Olivia Wilde and Mischa Barton Olivia Wilde and Mischa Barton

Just as we like to think those kids at Harbor High School do, The O.C. creator Josh Schwartz has learned a few important lessons from the show's second year, which culminated in Marissa's shocking shooting of Trey. So when Season 3 premieres on Sept. 8, some things may seem the same, but will be very different by the time the show is forced to take a break during baseball playoffs.

"Episode 1 is like Part 2 of the season finale," he says. "We're sort of there to resolve all of the story lines and get you back up to speed with where all of our characters' heads are at. But with Episode 2, you'll start to meet a lot of our new characters." Those include Eric Mabius as Harbor's new "mean dean," Autumn Reeser as opportunistic socialite Taylor Townsend and Jeri Ryan as a rehab pal of Kirsten's. Schwartz, though, does not foresee leaving fans with a big fat cliff-hanger before the break. "We've done that before, in our first season, after Marissa OD'd in Tijuana," he notes. "But we have had so many cliff-hangers lately that we're looking at that final episode before baseball as more a signal of the show being in a new place. You'll get a sense of, 'Oh, the show has moved over the course of the first four episodes,' and have a sense of where we are headed when we come back."

You can also expect fewer titillating twists, like the girl-girl kiss (and subsequent romance) between Marissa and Alex (played by Mischa Barton and Olivia Wilde). "That was a double-edged sword for us," Schwartz admits, "because we were asked to pull back [on the duration of the kiss] while at the same time it was very heavily hyped. It was like some sort of game. But while everybody thought the kiss would be the start and end of it for them, for us it was really about doing a real relationship and showing how, after it ended, Marissa would be at a place of greater maturity."

Speaking of Marissa — and aren't we always? — what will be the aftermath of her aforementioned marksmanship? Schwartz, arguing against criticism that the show's arcs are too short and too tidily wrapped up, hopes to get more mileage from what happens next. "It's funny, because people say, 'Oh, you resolve things too quickly,' and others say, 'You took too long.' But the Trey-shooting story line and the Kirsten story line play out for at least a half dozen more episodes.

"On the Trey side of it," Schwartz continues, "although the immediate plot and mechanics are resolved in the first episode, the emotional ramifications actually play out for a very, very long time. They set in motion plotlines that carry us through most of the season. [We'll explore] the fallout and how it lands on the characters and relationships — between Ryan and Marissa, especially."

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