Ben McKenzie and Rachel Bilson, The O.C.
With Mischa Barton's Marissa gone, graduation over, and Kaitlin Cooper back in Newport for good, can The O.C. remain as juicy and scandalous as ever? You bet it can. With Marissa's death and everyone dealing with it in their own way, there's plenty of room for relationship turmoil, new story lines, and guest stars to stir the pot.

When Season 4 premieres (Thursday, Nov. 2, at 9 pm/ET, on Fox; now streaming at MySpace.com), the twisted O.C. family is displaced and obviously changed five months after the season finale's fatal accident. With the very first glimpses of Ryan, it's hard not to think back to his Chino days, and with Summer starting her first semester at Brown University, things for the fake-tan-loving freshman have clearly changed since she's left Newport. "I really like the direction they pointed [Summer] in," her portrayer, Rachel Bilson, tells TVGuide.com. "Dealing with her best friend’s death, she turns into a tree-hugger, which is nice to see on a TV show, especially one with such a young audience. If they’re not aware of these things, it brings it to their attention, and maybe [they'll] want to get involved."

With a new life 3,000 miles away and a new perspective, there has to be a new character in Summer's life, right? Right. Everwood's Chris Pratt guest-stars in several episodes this season as a spiritual guru named Che, previews series creator and executive producer Josh Schwartz. When asked if Che will be a love interest for Summer, Schwartz says, "If he were to have a romantic story somewhere further on in the season, it would be with someone you might not expect."

The things we can expect from the new season? According to Schwartz, it will be a roadblock-free season for Sandy (Peter Gallagher) and Kirsten Cohen (Kelly Rowan), familiar faces such as Jimmy Cooper (Tate Donovan) will return, and Marissa, even after death, is still a big part of the show. "She will be very much in the fabric of the show," says the exec. "[Mischa] was an important part of the show and her character is honored in the beginning of the coming season."

But even with Barton's departure, Bilson doesn't feel she has to pull the weight. "We have a really good female cast, as well as male of course, and everyone shares the limelight," she says. In no way replacing Marissa, Willa Holland's Kaitlin Cooper certainly makes her mark in Newport. "She serves as a reminder to Julie that 'you still have another daughter. I'm still alive,'" says Schwartz, who also tells TVGuide.com that Kaitlin will have a romantic story line with hip-hopper Chris Brown in the second half of the season.

Another female stepping up to the plate is Autumn Reeser (like Holland, now a series regular), whose Taylor Townsend has grown from a know-it-all loner to a good friend. Going through her own relationship turmoil, Taylor returns in Season 4 with a big secret, and unexpectedly inches closer to Ryan, of all people. "Taylor is the ideal person to pull Ryan out of the darkness and towards the light," teases Schwartz.

And let's not forget the most fiery of Newport's females, Julie Cooper (Melinda Clarke), who even as she mourns the loss of her eldest child, finds ways to drag trouble around on her heels. "Four words: Julie Cooper, Urban Cougar," Schwartz says of the path he has planned for her this season.

But will this all be enough? Will Ryan's broody demeanor and Summer's environmental speeches keep The O.C. alive and bitchin'? Can Seth ride the comic-book train while keeping viewers caring? And, perhaps most importantly, with its many changes and turns, can the Fox sudser survive against ABC's Grey's Anatomy? (Ahem, look out for a connection between the two shows in the beginning of the O.C.'s new season....) Neither Schwartz nor Bilson seem concerned. "We don't know that it's the final season," says Bilson. "No one thinks it's over and no one wants it to be, because we really have this great thing."

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