In the season three opener, we start off with senior year starting in a few days. It has been a couple of months since the shooting. Trey has been in a coma all this time leaving the D.A. impatiently waiting for his side of the story. Feeling the pressure from the community the D.A. continues to put pressure on Ryan, Marisa, Seth, Summer and others for more information. 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 Marissa tries to plan this year’s carnival but is having much difficulty due to a little pest named Taylor. Sandy is surprised to find Kirsten has been released from rehab but instead of informing him, she has been living with another woman named Charlotte who she met in rehab. Julie and Sandy meet with the Dean and Dr. Kim to discuss Ryan and Marissa’s future at Harbor High. 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 struggles with attending a public high school, and her new friends make Ryan jealous; Charlotte's ruse is up when she learns that Kirsten did not inherit any money from Caleb; Julie's mansion is repossessed, leaving her with nothing; Taylor's power play dethrones Summer as commitee chairman, who then learns an interesting secret about her and Dean Hess.

Ryan decides to make a life-changing decision that Sandy reluctantly supports; Marissa looks to her new friends to help with her latest crisis with Ryan; Summer and Seth go on a mission to reveal a secret between Taylor and Dean Hess; Charlotte makes Julie an offer that she can't refuse.

Marissa discovers something in Johnny that Ryan lacks and Charlotte convinces Julie and Kirsten to throw a charity event. After discovering fake IDs in Charlotte's purse, Julie confronts her.

When the gang heads to The Bait Shop to see The Subways, Taylor's horsing around causes a major rift between Seth and Summer. Marissa, determined to end the potentially explosive rift between Ryan and Volchok, does whatever it takes to watch out for Ryan. Meanwhile, Matt, Sandy's Newport Group partner, goes above and beyond the call of duty when he learns he has to cut Newport Group staff.