Although Tate Donovan made a few appearances as Jimmy Cooper, he was not credited as part of the main cast for the season. continues to put pressure on Ryan, Marissa, Seth, Summer and others for more information.Mischa Barton left the main cast after the death of her character, Marissa Cooper. Trey has been in a coma all this time leaving the District Attorney impatiently waiting for his side of the story. Meanwhile Julie is steaming mad because Caleb’s accountant won’t give up the goods on Caleb’s will and Kirsten is still in rehab.Social Chair Summer tries to plan this year’s carnival but is having much difficulty due to a little pest named Taylor.
Later Ryan and Marissa partake in a similar meeting.
Elsewhere Jimmy meets a man and feels more than open to discuss his money problems with him.
Jimmy must make once more the difficult decision to leave or stay with his family; Kirsten returns to the Cohen household while Charlotte has to leave her house; Marissa and Ryan face a possible separation; Taylor lords over the school musical and makes Summer and Seth her stooges.
Marissa begins her first day at Newport Union Public School and Ryan doesn't seem to take a liking to the new friends she's made; Charlotte's true intentions towards Kirsten are revealed; Summer finds out the horrifying truth between the Dean and Taylor; Kirsten has a big decision to make regarding the Company.
Ryan decides to make a life-changing decision that Sandy surprisingly supports, and Marissa turns to her new public school friends for help with Ryan.