It's her eighteenth birthday, but Brooke soon realizes that she has no one but Rachel to celebrate it with. Meanwhile, Nathan continues to struggle with memories of the accident and Dan continues to be haunted by remorse over his actions against Keith.

Peyton spends more time getting to know her newfound brother, Derek. Meanwhile, Lucas gives up on his love for Brooke and Rachel tries to start a romance with Nathan.

Rumor surfaces that Brooke might be pregnant, causing Karen to worry as she fears that the baby might be Lucas'. Meanwhile, Rachel continues to get closer to Nathan when she confesses that she saw Keith during the accident.

Nathan gets two surprises in a row, and everyone is eager to share their advice with him. Deb also shares something she picked up. Brooke decides to celebrate while Peyton is being attacked by her stalker.

It's Prom day, and emotions are flying high at Tree Hill. An emotional Haley confronts Nathan about the sex tape and asks for a list of all his past sexual encounters. Meanwhile, an angry Peyton asks Lucas to skip the dance altogether, but he refuses to take no for an answer. Finally, Brooke and Peyton let out all their tension in a confrontation that can tear them apart forever.

It's Prom night, but things start to go awry as Lucas discovers who was the person in the hallway when Keith was killed, and psycho Derek holds Peyton hostage at her own house. Meanwhile, Haley and Nathan vow to be romantic with each other throughout the night, and Dan continues to win over Karen's affections.

Brooke and Peyton finally rekindle their friendship, Nathan's past mistakes continue to haunt him and Haley, and Lucas hears a shocking confession from the witness to Keith's murder.