During the last days of summer before college, Seth is working at a comic book store in Newport. Ryan has problems dealing with the issues of the past and pushes himself with his new job. Kirsten is preparing Ryan a "care package" but neither she nor Seth can persuade Ryan to come home since he moved out after Marissa's sudden death. At Brown University, Summer settles into her new dorm room with new friend Che, who's an activist who wants to rally the students for a protest. Taylor phones Summer from the Sorbonne in Paris to ask about her current living status.
Thanksgiving! Julie and Neil have relationship issues, but she is unwilling to talk about it. Seth has a new friend. Julie is informed on the movements of Volchock.
Summer soul-searches during a visit from Seth. Taylor pleads for Ryan's help with her marriage. Sandy longs for a guys' night. Julie vows to turn over a new leaf in moving on from Marissa's Death.
Ryan can't sleep, and a smitten Taylor tries to seduce him by becoming his sleep therapist. Meanwhile, Seth vows not to call Summer, and Kaitlin struggles when Julie has a fling with her tennis instructor.
Summer gets kicked out Brown, thanks to her friend Che. Ryan has fantasies about Taylor after kissing each other. And Kaitlin throws a party at Dr. Roberts house to get even with a popular girl.
In a parallel universe, Sandy is married to Julie, Kirsten is Mrs. Jimmy Cooper, Summer is engaged to Ches, and Seth is in full geek mode. And Ryan and Taylor, stuck there after a fall, must change it.
Seth is clueless about what to do for New Year's Eve. Solution? Crash the Ryan-Taylor road trip to Vegas. Now add pregnancy tests, a space alien rave, thefts, misunderstandings, pursuits and a marriage proposal and it's time to welcome 2007!
Warm hearts, cold feet: Seth and Summer each look for a way to call off the wedding. Who will crack first? Ryan's biological father plays the Big-C Card in hopes his son will see him.
Taylor's ex-hubby writes a hot-selling erotic novel. Who's the lead character? Three guesses and the first two don't count. Seth seeks Neil's permission to marry Summer. Kirsten uncovers Julie's biz scam.
Take her, I want her. Ryan overcomes his indecision and competes with Henri-Michel for Taylor's affections. Che leads Seth on a trek of spiritual renewal. Embrace your inner otter, Seth! Meanwhile, Kirsten and Julie have to do some damage control.
Seth and Che get in some trouble with the police when Che drags Seth into helping him try to free a groundhog before Newport's annual Groundhog Day festival. Meanwhile, Kirsten gets some life altering news and Taylor gets some extra help from a therapist to make things different with Ryan.
Seth and Summer come upon a fortune teller whose prediction makes the two question whether they are truly meant for each other. Ryan gets back in touch with his father (with a little help from Taylor). When the two teens discover a love connection between Frank and Julie despite her pending engagement, a Valentine's competition is sparked between "Team Bullit" and "Team Frank". Meanwhile, with a new baby on the way, Kirsten finds herself dwelling on an old secret involving Jimmy Cooper.