Frustrated by Lucas' growing popularity at school, Nathan searches for Lucas' weak spot, and finds it in Haley. Meanwhile, Peyton is furious with Lucas for submitting her drawings to the local newspaper without her knowledge.

Lucas asks Keith to play with him in the annual "Father and Son" basketball game, and realizes he got the better father figure after Dan publicly humiliates Nathan on the court. Also, Peyton has a hard time dealing with the anniversary of her mother's death and finds a comforting ally in Whitey.

On the night of Dan and Deb's annual basketball appreciation party stirs up old wounds and new feelings as Karen makes a new friend, Keith faces off with his younger brother once again and Lucas finally makes his move on Peyton. Also, Haley and Nathan grow closer until Brooke spreads a vicious rumor that leaves Haley devastated.

After fighting with his father and Haley, Nathan succumbs to the pressure he is feeling and takes amphetamines to help his game. However, he isn't prepared for the destruction the drugs do to both his body and his family. Meanwhile, Peyton goes to Lucas to rekindle their relationship, but when she arrives at his house, she catches him with Brooke.

Unable to handle the pressure from Dan, Nathan decides to quit the basketball team and looks to Haley to help him fill his free time. Meanwhile, Brooke becomes increasingly jealous of Lucas and Peyton's growing friendship.

Aside from a love for hoops, it would seem that Lucas and Nathan are two young men with little in common, but they are bound by the dark secret that they share the same father. Nathan is the star of the high school basketball team and local town hero, while Lucas is the only child of a single working mom. Now the two boys' lives collide when a twist of fate puts Lucas on Nathan's team and the half-brothers compete, not only for control of the court, but also for the heart of Nathan's beautiful girlfriend Peyton.

After his near-death experience, Lucas decides he made the wrong choice between Brooke and Peyton so he breaks things off with Brooke and secretly rekindles his romance with Peyton. However, the truth becomes obvious after he is rushed to the emergency room again and the girls come face to face in the hospital. Meanwhile, unable to pay his mortgage after paying Lucas' hospital bill, Keith puts his garage up for sale.

The gang hits the road to Charlotte where Brooke is determined to win first place at the annual cheerleading competition, but when one of her squad falls ill, Peyton begs Haley to step into the cheerleader's shoes for a day. Meanwhile, after Whitey assigns Lucas and Nathan to the same room, tempers flare and Haley is caught in the middle.

Lucas must make a difficult decision regarding Brooke. Haley considers having sex with Nathan.

Lucas is shocked to learn that Dan once asked Karen for joint custody of Lucas when he was a baby. Meanwhile, Peyton panics after Nicki kidnaps Jake’s baby while she is babysitting.

With the assistance of Peyton and Brooke, Lucas throws Nathan and Haley a wedding reception. Although Haley's parents support the marriage, Deb has a difficult time accepting it. Meanwhile, Dan's recent heart attack causes him to try and mend his relationships with Deb and Lucas.

After Dare Night resulted in new arrangements, a midnight meteor shower finds Lucas sharing a romantic night with Anna. Andy surprises Karen with a dinner and Keith cooks for Jules on their first date. Brooke finds herself forming a mutually beneficial relationship with Felix, and Peyton sets out to find an opening act for her club.

The girls of Tree Hill have a slumber party, at which time secrets are revealed and bonds are made. Meanwhile, Nathan and Lucas road trip to Charlotte for a basketball game, and unknowingly to Lucas, they embark upon free HCM tests, a genetic heart condition that Dan maintains. Karen and Andy have a row.

Nathan is concerned about Lucas' health, so he tells Karen that Lucas didn't take the heart test. Dan offers Keith to continue working at the dealership-as vice president. At school, Peyton must confront the rumors going around that she is a lesbian. This affects her friendship with Anna. As for Nathan and Haley, they begin to grow apart...

Nathan comes clean with Haley about his past relationship with Taylor, although Haley continues to email Chris without telling Nathan and Taylor finds out. Lucas and Karen remain at odds over his refusal to take the HCM test. Keith proposes to Jules. Meanwhile, Brooke fights for better working conditions at her new job. Lucas decides to take the HCM test.

As his marriage with Haley continues to go wrong, Nathan goes into a emotional crisis and becomes the "bad" Nathan of the past. Karen continues to struggle and try to figure out what would cause Lucas to move in with Dan. Peyton and Jake's relationship gets greater.

Keith and Jules' wedding day, and the event has turned the town upside down. Brooke asks Lucas to take her to the wedding as his date, Nathan makes an important decision involving his marriage to Haley, and Jake and Peyton take a big step in their relationship. Meanwhile, Karen and Andy discover Jules' secret relationship with Dan.

On his way home from seeing Haley, Nathan stops to visit Taylor hoping for some fun and maybe more. Meanwhile, Anna gets a surprise visit from her ex-girlfriend and is inspired to tell her parents about her sexuality. Also, Lucas works with Andy to bring Dan down, Karen puts her foot down with Brooke. Peyton and Jake continue to hide baby Jenny from Nicki.

Lying in a coma after his race car accident, Nathan dreams of what life would have been like if Dan had stayed with Karen and Lucas instead of marrying Deb. In this imaginary world, Lucas would have had the wealth and stature and Nathan would have been the one growing up on the wrong side of the tracks. After waking up, Nathan phones Haley and tells her he doesn't want her to come home.

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.

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.

It's Halloween in Tree Hill and everybody is celebrating at Tric, with special guest band Fall Out Boy. The masquerade ball gives the opportunity to Haley to win back Nathan while Brooke is trying to seduce Lucas. Also, Peyton decides to face her new mother and get to know her; Dan uses blackmail to become mayor but things don't turn out as easy as he thought they would when Deb gets in his way.

Brooke makes a "Fantasy Boy Draft," after all of the cheerleaders are fighting over the same guys. Haley and Peyton continue to argue over Nathan. Dan butts heads with Karen because the election is drawing nearer. Lucas is trying to keep up with the fast pace of basketball.

As the town readies for the Ravens' first basketball game, Lucas worries that his head and heart aren't in it. Nathan accuses Lucas of being the Ravens' weak link. Peyton and Haley mend fences to support Brooke in a time of need. When the mayoral race tightens, Dan resorts to a smear campaign.

Lucas and Peyton take a road trip together to find Ellie. While out of town, Lucas reconnects with a friend from his past. Brooke, Haley and Mouth successfully launch the Clothes Over Bro's website, only to find that demand far exceeds supply. Deb reveals to Nathan that she tried to kill Dan.

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.

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.

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.

Lucas attempts to play in the first game after Keith's death, but cannot bring himself to do it; Nathan and Haley prepare to renew their vows, while Mouth tries to get closer to Rachel; Peyton receives a surprising offer; and Brooke finds a way to get revenge on Rachel.

Haley argues about her wedding dress with Brooke during the rehearsal dinner. Elsewhere Karen and Lucas arrive back in town.

And Peyton is surprised by what she finds...

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.

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.

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.

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.

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.

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.

When Mouth and Rachel's road trip goes wrong, the other teens go out to their rescue. While on the trip, Nathan and Haley get a second chance to enjoy their Prom and Peyton and Lucas decide to take their relationship to the next level. Finally, Brooke reveals the truth about the stolen calculus exam to Haley.

As the end of the school year approaches, Peyton considers participating in a music internship in Los Angeles, while Brooke tries to reconnect with Chase through yearbook signatures, and Haley struggles to write her valedictorian speech. Meanwhile, Dan suggests that Lucas get professional help when Karen worries about his obsession with theories about Keith's murder.

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.

It's four years into the future and the Tree Hill gang has finished college. Now, their lives have taken completely different directions. Lucas has written and published a book, Brooke has made it big in the fashion industry with her brand "Clothes Over Bro's", Peyton is pursuing a career in the music business, and Nathan and Haley continue to raise a now older James.

Now that Peyton and Brooke are back in Tree Hill, Lindsey worries that the two might threaten her and Lucas' relationship. Meanwhile, Nathan visits Dan in prison (his first visit in four years) and gives him a picture of his grandson. Meanwhile, Haley tries to persuade Quentin to return to school, Brooke opens her store in the old Karen's Cafe and Peyton signs her first band.

In this flashback episode, memories are looked back upon. Lucas surprises Peyton in Los Angeles and they talk. He asks her something and is left with a surprising answer. Meanwhile, Nathan's temper triggers up after a guy reminds him of his cheating in high school basketball games.

The Honorary Title performs at Tric and Mia plays her song there as well. Carrie tries to get closer to Nathan. Brooke sets Mouth up on a blind date with her assistant and Lindsey confronts Lucas about Peyton.

Haley, Brooke, Peyton, Lindsey and Mia get locked in the Tree Hill High library on the night of the Ravens' first game. Also Brooke tries to stand up for her mother, while Lucas and Nathan discuss whether to tell their loved ones about their indiscretions.

On the eve of Lucas and Lindsey's wedding, they conspire to save Nathan and Haley's marriage. Brooke pairs Peyton with an old boyfriend, while Rachel and Dan return to Tree Hill.

Lucas picks up the pieces after being left at the altar by Lindsey, while Nathan and Haley deal with the repercussions of Jamie's abduction. Dan is free for now, but he must find himself a job to convince the parole that he is changed for good. Brooke is haunted by her past as a woman from adopting asks her questions, while Peyton gets a visit from an old friend.

Nathan and Haley throw a birthday party for Jamie. Deb hired a clown, and Haley is not happy with it since it's a creepy one. Lindsey returns to Tree Hill for Jamie's birthday, which gives Lucas hope that the relationship will be rekindled. When Dan arrives, Deb's mood swings fast and in the meantime Brooke and Peyton attend the party with baby Angie.

Lucas is crushed by devastating news. Quentin is pushed to his limits during a Ravens game. Dan's is second on the donor recipient list to get a new heart. Haley thinks about her decision to release a new album while Brooke's baby undergoes emergency surgery and a shocking truth stuns Peyton, told by Lucas.

In the sixth season premiere, Tree Hill residents must make a decision that will change their lives forever. Lucas finally pursues his dream with the woman he loves, Brooke must face a reunion with her mother, Mouth makes a revelation, Nathan and Haley must face a ghost from their past and the news of Dan's accident is slowly beginning to spread.

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.

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.

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.

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.

Lucas falls asleep and dreams of a 1940s Tree Hill were he owns Karen's Cafe. Here, Dan is a dangerous mobster and everyone is entangled in his web: Brooke owes him money, Mouth is searching for proof that would link him to Keith's murder, Haley is his former lounge singer, and Lucas is in love with his step-daughter Peyton.

Peyton shares some startling news with Lucas, who discovers that Julian has been keeping another secret about the movie. While searching for runaway Sam, Brooke is forced to confront her lingering feelings over her attack. Nathan struggles with his new professional environment.

Lucas and Julian have a difficult time finding the right director for their movie. Meanwhile, a present from Lucas confuses Peyton and Brooke battles with romantic complications.

Peyton and Lucas deal with shocking news about Peyton's pregnancy as Brooke and Julian face a crossroads in their relationship. Meanwhile, Nathan and Haley celebrate their anniversary, with Dan and Deb babysitting Jamie; and Mouth and Millie work to redefine their relationship.

While Julian makes Brooke a surprising offer, Lucas takes Nathan and Jamie to an important place from his past. Meanwhile, Peyton prepares for the future; Sam and Jack go up against the principal who fired Haley; and Skills and Mouth go on a road trip to help Mouth forget Millie.

Nathan and Haley both face their dreams as he questions his ambition to play in the NBA and she receives an offer from Nick Lachey. Meanwhile, Brooke learns something that could change Sam's life forever, Jamie attends his first school dance, and Lucas and Peyton take a road trip.

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.