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.

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.

The search for Nathan becomes increasingly dangerous, and Dan’s life hangs in the balance. Brooke is surprised when her father returns. And Clay and Quinn reconnect with Logan.

Nathan worries about Haley as they prepare to renew their vows. Peyton and Brooke's friendship becomes strained and Deb confesses to Dan about the fire.

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.

In the final chapter of One Tree Hill, the tenth anniversary of Tric brings old faces and new possibilities for the Tree Hill family.

A class assignment reveals the deepest secrets and desires of Lucas and the students at Tree Hill High. Worried about college prospects, Skills turns to Haley, while Nathan wrestles with Deb's suicide attempt. Chase learns that Brooke cheated on her calculus exam, while nudity and drugs run rampant in the halls of the school.

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.

Tree Hill bids goodbye to the past while anticipating the future: Lucas and Peyton prepare for the birth of their child with the help of a surprise visitor, Dan nears his end, and Brooke works with Victoria to relaunch Clothes Over Bro's. Meanwhile, Nathan returns to Tree Hill to face Haley and Jamie after being released from the Chiefs.

On Lucas and Lindsey's wedding day, Peyton must choose between intervening and losing Lucas forever. Nathan uses the event to try to mend his marriage to Haley. All are shocked when Dan, who is out of prison on parole, shows up at the event.

A storm strikes Tree Hill, putting everyone's life in danger.

Dan, Julian and Chris Keller attempt to rescue Nathan. Brooke’s conflict with Xavier escalates. Quinn and Clay revisit the past.

A violent rainstorm knocks out the power in Tree Hill, leading Haley to Nathan's doorstep and Brooke out into the downpour for a dramatic confrontation with Lucas. Peyton finally confronts the truth about Ellie's illness, while Mouth is tempted by his new friend, Rachel. Before morning, secrets are revealed, relationships are tested, and new love gets hotter than ever.

The aftermath of the school shooting and the death of Jimmy Edwards forces everyone in Tree Hill to examine their lives. Nathan reassesses his relationship with Haley, while Brooke and Rachel join forces to heal the student body. Dan must deal with the ramifications of shooting Keith, while Lucas and Peyton consider the implications of their kiss in the library.

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.

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.

Lucas and Peyton's wedding day finally arrives, bringing some surprise guests along with it. Haley finds herself playing an unexpected role in the ceremony, as Skills and Brooke try to control Jamie and Nick. Meanwhile, Nathan continues to hope to be drafted into the NBA.

Dan brings Renee onto his television show, leaving Nathan and Haley powerless to stop him from revealing the truth of her pregnancy to the world. Quinn examines what went wrong with David, and Sara and Clay discuss their past. Meanwhile, Brooke comes clean with Julian about her true desires.

When Whitey throws Lucas and Nathan off the bus due to their misconduct on the basketball court, not only does it leave the two brothers stranded 30 miles from home, but they encounter a carload of punks who threaten them with a gun. Injured during the game, Brooke needs Peyton to drive her home and in, an unlikely turn of events, Peyton asks Haley for help. Meanwhile, Karen and Keith attend a business function and tempers flare when Dan and Deb are seated at their table.

Lucas and Nathan bear the brunt of Dan's abuse as he coaches them into the playoffs, pushing both of them to their breaking points. Haley is stunned after Dan threatens her, causing her to reconsider her relationship with Nathan. Meanwhile, Whitey learns that his medical condition may be more serious than he first expected, and Dan learns a shocking secret from Deb.

In the second part of the this seamless 2-hour Season Finale of "One Tree Hill," things heat up between Lucas and Brooke since he finally tells her what he feels about her. Nathan and Deb conspire to desert Dan for good, leading to an explosive conclusion when he discovers their plan. Peyton has a shock. Meanwhile, Karen decides to spend the summer holiday in New Zealand. And at the climax of Dan's numerous deceptions someone sets the dealership on fire with him in it.

It is revealed that Lucas knows who tried to kill Dan and he confronts the guilty party. Brooke, Peyton and Haley find themselves behind bars. Peyton finds her guilty conscience on the surface. Chris Keller convinces Nathan to be his wingman at a high-stakes poker game. The residents of Tree Hill finally choose a mayor.

When someone unleashes the students' time capsule upon Tree Hill High, Lucas and Mouth must confront a person from their past. Brooke has to deal with the revelation that secrets aren't the only things she exposed in the time capsule. Dan learns to forgive Keith. Haley is forced to reconcile the man Nathan was before with the man he has become, and Peyton's Breast Cancer Benefit Concert at Tric features performances by Haley, Jack's Mannequin and the return of Fall Out Boy.

As graduation approaches, Haley prepares for the recital of her valedictorian speech and motherhood. Nathan must adjust to life without basketball, while Brooke makes a confession that may have great consequences. Lucas confronts Dan after Karen's life is threatened.

The Tree Hill residents are forced to face their fears as Dan turns over on a new leaf and Brooke taking the hardest decision of her life. In the meantime, Haley's career takes a turn and Peyton is visited by somebody from her past. Mouth and Millicent meet a new face. With all, Lucas and Brooke help each other through the struggles.