As West Beverly prepares itself for the annual prom, Annie, Adrianna, Naomi, and Silver go out shopping together for the right evening gown to wear and try to get all glamored up for the event by visiting a famous hair stylist. A dateless Annie agrees to attend the event with the socially awkward Charlie, who has a massive crush on her. However, when he realizes that Annie is only interested in being friends, Charlie turns against Annie... showing his true repressed psychopath colors to plot a cruel revenge. Naomi attends the prom with Liam while she learns that Jen has emptied out her trust fund to support them living at Jen's new house. Meanwhile, Dixon is nominated for prom king, while Ethan learns that he has been accepted into lacrosse camp for the summer. Also, both Kelly and Harry take action to help Liam get on the right track, while he continues to try to temp Annie to embrace her own dark side as he has with his own. Ryan grows more closer towards Jen, and he also ignores Kelly's warnings that Jen is a devious, sociopath seductress whom is using him for self interest. At the prom, Harry informs the students in attendance that any after-prom activities will be dealt with punishment, while Navid provokes a fistfight with Ty when he reacts with indifference over the pregnant Adrianna's unborn child which is in fact his. When Silver learns that Dixon has nominated himself for prom king, she decides to enter for prom queen as a write-in candidate and finally gets to speak her mind to the attendees.

During the summer, most of the students at West Beverly were forced to attend summer school after Annie anonymously called the police to report Naomi's post-prom party. During the last weekend of Labor Day, Naomi, Silver and Adrianna hang out at the Beverly Hills Beach club. There, Adrianna runs into an old boyfriend named Teddy Montgomery, a tennis player and new student, while Naomi finds him irresistible. Navid also plans on spending his first romantic night with Adrianna, but jealousy gets in the way. Meanwhile, Annie has spent the summer isolating herself out of guilt for the hit-and-run accident that she committed, fearing that someone will discover her terrible secret.