Brooke has an end of the summer party on the beach. As Nathan comes home from basketball camp, Haley tries to tell him how she feels.

Elsewhere Lucas deals with Brooke's rules for dating and Peyton deals with family issues.

Due to the aftermath of the release of the time capsule, chaos breaks out. Someone is holding students of Tree Hill hostage with a gun, shooting. While lives hang in the balance, Nathan and Lucas put themselves at risk to protect their friends and loved ones. Young lives are shattered and two lives will end.

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.

Nathan struggles with money problems and reluctantly asks Dan for help. Elsewhere Brooke learns the new man in her life is also her new English teacher. Peyton gets help from an unexpected source, and Lucas returns to the Ravens just in time to help the team advance in the playoffs for the state championship.

Peyton returns to school, but she breaks down. In the meantime Nathan is cornered into a no-win situation by Daunte. Brooke's fashions are a hit at the local show. And Deb takes drastic action for her addiction.

Derek tells Peyton to give Lucas a chance just as Brooke tries to make up with him. Rachel asks Haley to tutor her when she discovers she is failing a class. And Nathan has more trouble with Daunte.

As the Ravens prepare for the championship, Lucas learns Nathan intends to throw the game and decides on a risky plan to even the odds. Karen insists Deb show up for her son's final game and tries to help her get there. Also Dan makes a last plea with Daunte.

After a cardiac incident, Lucas has a dream in which the spirit of Keith visits and shows him how much one life can affect the lives of others, with a nod to “It's a Wonderful Life.” Elsewhere, Hayley is the victim of an accident and Dan helps out Nathan.

Dan must face the harsh consequences of his decision to murder Keith as Karen and Haley's pregnancies complicate the lives of Nathan and the graduating seniors of Tree Hill High. Lucas wrestles with his post-high school options, and Peyton and Brooke prepare to spend the summer in Los Angeles together.

When tragedy strikes in Tree Hill, Nathan and Haley experience difficulties breaking the news. Brooke still hurt over the robbery, questions her friendship with Peyton, and Lucas and Skills finally meet Quentin's mother.

Brooke takes a trip to New York with Victoria. Peyton begins connecting with Mick Wolf, who begins telling stories about her parents. Haley continues having problems with a student and Nathan is confronted by a vision of Quentin.

Nanny Carrie continues to wreck havoc when she puts both Haley and Jamie's life at risk. Lucas reunites with Lindsey for a business meeting. Meanwhile, Brooke struggles for power at "Clothes Over Bros" after Victoria continues making unexpected decisions.

As Lucas sets out on his book tour, he runs into a person from his past. Nathan finally gets a chance to prove himself on the court, but begins to question his health as he does so. Meanwhile, Haley reaches out to a student; Brooke debates a life-changing decision; and Peyton confronts Mick over his true identity.

Nathan and Haley must team up to help Jamie deal with a school bully. Meanwhile, Lucas and Peyton continue to adjust to life as a live-in couple. Elsewhere, Mouth tries to get his old job back.

Lucas' novel receives interest from a suprising person, as does Mouth as he meets his new intern. Jamie begins to develop a crush on Sam and her rebellious ways, while someone becomes enamored with Brooke. Meanwhile, Haley and Nathan discuss his return to baskeball as his comeback begins to look more like a reality.

Sam teaches Jamie about money. Brooke must decide whether to date Owen again, since he broke her heart the last time. Nathan comes face to face with an old rival. Meanwhile, Lucas' novel forces him to make jeopardizing decisions, and Peyton meets the movie producer, Julian.