By Daniel Barron for AllPop

Things are great in Newport. Ryan and Marissa are doing great, as are Seth and Summer. In fact, Seth himself felt a pimple coming on the night before and wakes up to find a clear face. Best of all - we're all treated to a great episode of the O.C. (finally!).

But Seth is worried. He has a theory that anytime things are going really well in Newport, trouble is ready to come a-knockin'.

How right he is.

No sooner do the words leave his mouth, then a chatty young lady rings the doorbell, to which Ryan answers. He has no idea who she is until Seth comes to the door and says the words iKaitlyn Cooper.i That's right folks. Marissa's younger sister is back from boarding school.

It's been two years since 'Mini Cooper' was in Newport and she apparently has no idea what has happened with her mom and the whole trailer park thing. Julie wanted to protect her daughter from everything while she was at boarding school but now it's time for her to fess up. Julie doesn't beat around the bush - she tells Kaitlyn what happened with Caleb and the financial problems and drives her to home sweet home. Kaitlyn looks less than impressed, but actually puts on a brave face. A few moments later, Julie leaves the room and Kaitlyn receives a call from an angry guy. She hangs up before he can get out what he wants to say to her.

Later on, Marissa is talking with the gang about how she misses Johnny and hasn't heard from him since she returned to The Harbor School. Ryan suggests calling 'Bizarro Seth', a.k.a. Chili. Marissa does just that and Chili, who knows how miserable Johnny is not talking to Marissa, hands the phone over to his best friend. He makes up a lame excuse about why he hasn't been able to return her calls, and she says he can make it up to her by meeting up with her and Kaitlyn and saying goodbye before he goes on tour with the surfing competition (Marissa still doesn't know that Johnny isn't going at all). Johnny grudgingly agrees.

Back in Adult-Land, Veronica Townsend calls up Kirsten, asking her to set Veronica up with Neil Roberts of all people. Kirsten has no idea why she would want to go out with someone who she insulted so badly the week before. Veronica states that he's an eligible bachelor (almost) and has lots of money. She tells Kirsten that she'll make Marissa's life back at The Harbor School horrible if she doesn't co-operate. Kirsten grudgingly agrees.

We then see sisters Marissa and Kaitlyn walking near the beach after an afternoon of shopping (at the thrift shop no less (vintage is in, right?!). Johnny and Chili show up and are introduced to the youngest Cooper, who gets an interesting gleam in her eye when she says hello to Johnny. The four go to the diner and when Chili and Marissa are left alone briefly the former tells Marissa about how Johnny lied about going on the surfing tour. Marissa is upset but Chili explains that Johnny did it for her.

Back at the Cohen's house, a strange guy shows up asking for Kaitlyn. The Chino in Ryan tells him something is suspicious about this guy so he lies and says he's never heard of her. The guy gives Ryan his name and phone number just in case he sees her.

Ryan then goes to the trailer park and confront Kaitlyn about this strange boy named Justin. Kaitlyn acts like she barely knows him. Ryan takes her word for it and agrees to take care of things for her.

Marissa later confront Johnny about his lying to get her back to The Harbor School. Johnny is angry that she gets upset and simply says 'I needed you to leave.' She's still apparently clueless about how hard it is for him to be around her while he's still very much in love with her. He then tells Marissa that he never wants to see her again. Good man!

The ever-reliable Sandy, meanwhile, is asked by Kirsten to help get Veronica on a date with Neil. Sandy doesn't know how Neil will ever agree to it but says he'll give it a shot because him and Summer's dad are friends. He calls Neil up and tells him straight up that Veronica wants a date with him and she'll make life horrible for Marissa at school if he doesn't agree. So....Neil does agree!

We meet back up with Ryan who, thanks to the number given to him earlier, calls Justin and meets up with him. He tells him to stay away from Kaitlyn and Justin is incredulous. He claims that she stole $1,500 from his friend back at boarding school and he's looking to get it back. Ryan isn't sure what to think now. He goes back to the trailer park confront Kaitlyn about the money. She denies taking it, but Ryan later finds an empty bag with the school name on it. He knows she took the money and confronts her once again. She fesses up, but says she took it because (and try following me here) a friend of the guy with the money got her friend pregnant but would have nothing to do with her, so Kaitlyn took the money to pay for an abortion. Once again, Ryan isn't sure what to believe.

Neil goes on his date with Mrs. Townsend and - surprise, surprise! - Julie ends up showing up at the same restaurant. She can't believe he's out at dinner with Veronica and she leaves the restaurant before Mr. Roberts can notice. Interestingly, Neil actually enjoys the date and asks Veronica to Kirsten and Julie's upcoming launch party for their new business.

Also going to the launch party now is Johnny, who was invited by Kaitlyn after Johnny arrived at the trailer park looking for Marissa, who wasn't around.

It looks like a lot of trouble could be brewing at the party. Julie tells Kirsten that she has feelings for Neil, so Kirsten scrambles with Sandy, Seth and Summer to somehow break Summer's dad and Veronica up. They're only too happy to oblige.

Downstairs, Justin and some of his friends show up very much unannounced looking for the money from Kaitlyn. Ryan threatens to call the cops and the kids, surprisingly, say they'll happily do the calling! Something isn't right and they all decide it may not be best to bring the authorities in. The kids turn around and find that Kaitlyn has disappeared...

...And Ryan and Marissa find her at the trailer, packing her stuff. They want to know what's going on and Kaitlyn explains that she knew all along about the problems with the Coopers. In fact, her whole school knew about Julie living in the trailer park and Kaitlyn stole the money so she could get home and make sure her family is okay. Mystery solved.

Back at the Cohen's house, Kirsten and Julie's dating service, New Match, is being launched. While this is happening, Seth is busy spreading an apparently nasty rumour about Mr. Roberts. He tells Taylor, who tells her mom, who proceeds to leave hastily. Neil is confused but ends up asking Julie out. What did Seth tell Taylor that freaked her and her mom out so much? Summer thinks it's that Mr. Roberts 'voted for Kerry' in the last election. Hmmm....

Johnny ends up meeting with Marissa and apologizing to her for everything he had done to upset her. Marissa tells Johnny it's okay and not to be a stranger. She also asks if he can do her a favour and drive Kaitlyn home. Now there's an accident just waiting to happen. The show ends off with Kaitlyn telling Johnny to pull over because she wants to swim. She throws off (most of) her clothes and runs into the water with Johnny hesitantly following behind.

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