The Newport kids plan an end-of-summer trip down to Tijuana, Mexico (aka "T.J."). Jimmy has plans of his own, which don't sit well with Marissa. Sandy gets a new job, which Kirsten can't understand. Summer, Seth, Ryan and Marissa find themselves in a strange place together. Jimmy takes it too far. Disaster strikes one of the O.C. kids.

Everyone is back home in Newport, and Marissa is recovering. Julie points her finger at Ryan and forbids him from seeing Marissa, who does not appreciate the help. Sandy starts his new job, but finds himself surprised by the case work. Kirsten finds herself surprised by Sandy's new co-worker. Ryan enrolls at his new school, with conditions. Julie gets an intervention, and Jimmy gets a new roommate.

Back to school for the O.C. kids. No one really wants to be there, except for the gossips. Ryan doesn't feel like he fits in at his new school, and Luke doesn't make the situation any better. Sandy accepts a case at his new job, a case that will test his relationship with Kirsten and her father. Anna and Seth hatch a plan. Marissa chooses her man.

Couples are plentiful in 'The O.C.' It is a night of firsts. Now that they are free to love one another, Ryan and Marissa plan their first official date. Kirsten sees her father with a new woman, and fears Sandy has found a new woman of his own. Seth takes matters into his own hands with a girl, and is taken by another girl.

It's Thanksgiving time in ‘the O.C.' It's time for family reunions, and Ryan gets called home by his family. Is it because of the holiday, or is it for a favor? Marissa decides to go along for the ride, but ends up going down Ryan's bad-memory lane instead. Seth plays the player role, but not very well.