 On Trey s 21st birthday, Marissa, anxious to help Trey and Ryan forge a relationship, throws a birthday party for Trey at the Cooper-Nichol mansion that turns out to be a rumble when one girl nearly drowns from a drug OD. Meanwhile, Seth is left in hot water by both Summer and Zach. Sandy wants to continue his friendship with Carter, leaving a confused Kirsten. Also, a distraught Julie shares some memories with her blackmailer Lance, and in the process learns a few things and gains a few ideas about the future of her marriage to Caleb.