With senior prom only weeks away, Haley's frustration over her injuries increases and Skills and Mouth hatch a plan to help Nathan earn money for the big dance by stripping. Brooke betrays Rachel in order to get closer to a new guy and Peyton and Lucas resolve to be happy. Struggling with her drug addiction, Deb makes a choice that could end her life.

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.

Haley confronts Brooke regarding the stolen calculus test. Lucas and Peyton consider taking their relationship to the next level as Peyton and Brooke grow closer. In Deb's absence, Nathan throws a senior party at the Scott House, where a sex tape from Nathan's past surfaces.

On the day of Prom, the residue of Nathan's pre-Prom party has serious repercussions for everyone in Tree Hill. Haley asks Nathan for a list of his past sexual conquests. Rachel is suspended after taking the blame for the exam she stole with Brooke. Peyton tells Lucas she wants to skip the Prom entirely, but he refuses to take no for an answer. Finally Mouth and Brooke must deal with dating Clean Teens on Prom night.

Peyton is scared by images of "Psycho Derek," so she decides to confront him. Meanwhile, Lucas continues seeking answers about his Uncle Keith's Murder.

Nathan and Haley grow closer in spite of the recent scandal. Brooke wonders if a spark might be rekindled with Chase. Peyton receives a tempting offer that would ultimately take her away from Tree Hill. Mouth reconnects with Gigi, while Lucas tells Karen that Dan is a murderer, setting off an explosive series of events.

As graduation day dawns in Tree Hill, some dreams begin as others end. Haley prepares for her graduation speech and her role as a young mother, while Nathan prepares for life without basketball. Brooke makes a heartfelt confession that puts her future in jeopardy. Lucas confronts Dan as Karen's life is threatened.

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.

Missing Nathan gives Jamie nightmares about Dan, who is indeed paroled. Lucas and Lindsay decide to 'coincidentally' have separate stag and hen nights at the same place, so Nathan and Haley are bound to meet. Brooke arranges a hot blind date for Peyton, but the joke is on her as Owen's chosen mate is Chase, Brooke's former 'clean teen' lover. Jamie's tireless efforts to get his mom and dad to make up In turn make Haley realize she shouldn't have tried to change Nathan. Ruthless business adviser and absent mother Victoria pushes Rachel out, to Brooke's disgust.

The marriage counselor's advice to reconnect with personal aspirations is followed to the letter. Haley is happy to re-enter the music field; Peyton is to sign her up for a record. Haley can't find an appropriate nanny, apart from Nathan's mother Deb. Nathan's come-back in basketball is harder to get going as the team's stupid star Q is rude and hostile. Only Jamie get's on with Dan, the brothers warn him to keep his distance. Brooke is ecstatic to be 'getting a baby', so she stocks up on toys etc.

Peyton shares shocking news with Lucas who is still in LA with Dixon and Julian. Nathan struggles to adjust to his new career and Brooke desperately searches for Sam.

As news of Peyton's condition spreads, Marvin and Millicent struggle to remain a couple and Brooke tries to suss out Julian's intentions. Peyton and Lucas babysit Jamie and his friend, while Haley and Nathan spend a night out together with Chase and Mia.

Nathan is on the bench during five losses, but has more maturity, team spirit and insight than the arrogant, selfish star scorer. He feels this is bound to pay off, as Dan predicts. After refusing six top directors, Lucas and Julian get an ultimatum from his father, Paul. He also tells Peyton that the infidelity she dumped Julian for was his publicity stunt. Julian is incredible patient with Brooke's insecurity. Chase is Mia's ideal playmate, inspiring a new single.

Julian offers Brooke tickets to move to L.A. with him and Sam. However, she keeps doubting and whining that she can't uproot Sam, although she's willing. Even Chase warns her not to waste such an opportunity. When Jamie asks about Keith, Nathan and Lucas take him to his auto-shop. Jack braves suspension to make all Haley's class walk out of Brumkin's boring English class. Even a college dorm PJ party can't console love-sick Mouth.

Nathan is offered a two year pro contract, but in Europe. He agonizes whether he should take it, as Bobby suggests, or stick to his NBA dream, as Haley advices. Jamie not only does well at his first school dance, he is the one who counsels 'babsitter' Skills to date his teacher there. While Peyton grumbles bedridden, Lucas repairs the Comet as a surprise, while both reminisce. Chase must convince Mia his affair with Brooke was and could only happen before them. Haley enjoys working with Nick Lackey, who wants her to produce music.

Peyton and Lucas' wedding day has finally arrived and surprise guests attend. Haley plays an unexpected role in the ceremony while Nathan hopes to be called up to the NBA. Antwon keeps Jamie on a short leash, and Brooke does the same with Nick Lachey.

Nathan gets some news about his future on the Chiefs. Peyton gives birth to hers and Lucas' baby daughter, Sawyer, and receive a surprise visit from Karen. Dan is on death's door, while Brooke and Victoria prepare to re-launch Clothes Over Bros.

A disgruntled Renee makes her pregnancy known in the national media. Quinn tells David that she wants a divorce and spends the night with Clay. Mouth quits his job at the station after he is forced to report on the scandal surrounding Nathan. Brooke's fashion show is a huge success but Victoria warns her about Alex and Alex's obvious designs on Julian.

Renee presses charges and has Haley arrested and thrown in Jail. Clay and Quinn grow close much to Nathan's distaste. Elsewhere, after a false start Julian and Alex begin to work on her script.

Julian gives Alex another chance and they continue to work on her script which he believes is very good but Brooke is not happy. Brooke reconnects with Chase to make Julian jealous and it works. Mouth gets to tell the truth on air about the allegations against Nathan much to his station manager's horror. Milicent begins to take weight loss tablets after Alex tells her she is a plus-size model. Elsewhere, Haley offers to pay off Renee unknown to her that Rachel and Dan have got to her first.

Haley returns to the stage much to Miranda's annoyance but the gig turns out to be a success and changes Miranda's attitude somewhat. Brooke believes she might be pregnant but is conflicted on how Julian will take the news - but the test proves negative. Julian finishes the script with Alex and heads out to be with Brooke at Haley's gig but gets a call from Alex telling him she's close to taking cocaine again so he goes to her much to Brooke's annoyance. Rachel and Dan arrive back in Tree Hill but his hoped reconciliation with Nathan doesn't materialize. But Dan isn't going anywhere. Mouth meets Rachel and tells her to try and reconcile her differences with Brooke but Brooke isn't having it. Mouth and Brooke are both concerned and angry with Millicent who's desperation to be liked by the public is putting her in a downward spiral. Elsewhere, Clay's hardball tactics with the Charlotte Bobcats and Nathan's contract fail when they sign another player to fill Nathan's spot. What will Nathan do now?

After losing his place on the Charlotte Bobcats Nathan reaches breaking point with Clay and fires him but this ends up causing a rift between Haley and Quinn with Quinn moving out to a hotel. Dan takes it badly that Clay messed up and tries to teach him a lesson by nearly drowning him in the surf. Later Clay is fired by his boss for stuffing up Nathan's contract. Victoria arrives unannounced and takes a liking to new TRIC bar manager Grubbs. Meanwhile, Brooke tells Julian that it is doubtful that she will ever be able to get pregnant and he promises to get different opinions and they will work it out. Elsewhere, Millicent's increased drug taking alarms Mouth and her model like tendencies and demands disgust Brooke. It prompts Victoria to call the police when she sees Millicent driving drunk. Millicent calls Brooke from jail but Brooke tells her she cannot help her.

Quinn's gallery opens with Clay very supportive unaware that he is being stalked by Sara lookalike Katie until she makes her presence known and Clay shows Quinn how alike Katie is to Sara. Josh's sex tape with Alex is emailed to Julian's father with a demand for $1,000,000 putting the film in jeopardy. Miranda finds out she is being deported thus putting a spanner in the works with Grubbs's recording but Grubbs finds a way around it by proposing to her. Lauren tells Skills that she has fallen for someone else but he is unaware it is his best friend Mouth until he sees a photo of them at the gallery where he promptly punches Mouth. Meanwhile, Victoria's affair with Alexander is exposed in more than one way. Elsewhere, Nathan and Jamie spend a guys evening together & later he asks Haley if she'd be ready to try for another baby. She tells him she took a pregnancy test and it was negative but is she telling him the whole story?

Quinn takes Jamie on a treasure hunt as an increasingly despondent Haley further withdraws from both Nathan and Jamie. Katie invades Clay's personal space convinced that she is his dead wife Sara. Clay plays along until he manages to have her committed. Mia breaks up with Chase by text and then comes back to Tree Hill to manage a heart-broken Grubbs after Miranda leaves. Julian shows his film to a delighted Brooke as he anxiously awaits confirmation on whether his indie film will be bought by a film festival.

Haley tries to overcome her depression by joining Nathan, Jamie and the rest of the Tree Hill gang on a trip to Utah for the premiere of Julian's film.

As the gang returns from Utah, Brooke and Julian are engaged, Haley learns that she is pregnant, Nathan must leave for training camp, and Clay and Quinn are assaulted and shot by Katie.

Clay and Quinn discover they've been shot, and as they fight to live, Nathan and Haley struggle with the situation. Meanwhile, Julian tries to preoccupy Jamie, and Brooke's legal troubles mount.

As Brooke deals with the mounting financial troubles at Clothes Over Bro's, Nathan and Haley come to a conclusion regarding Nathan's career. Meanwhile, Julian begins a new film project, while Alex and Chase spend the afternoon together.

As Clay is discharged from the hospital, Nathan contemplates walking away from the NBA. Meanwhile, Brooke and Victoria disagree on how to handle the company's financial problems, and Chase discovers a secret about Alex.

As Halloween approaches in Tree Hill, Brooke and Julian get an unexpected visitor, and Nathan begins a new career. Meanwhile, Clay and Quinn struggle with life back at the beach house, and Haley and Mia host an open mic night at Tric.

Nathan is furious when his first mission as Clay's junior agent seems to go wrong because of his lack of jargon knowledge, but he actually lands the football client. Julian accepts Alex's suggestion to assemble all potential best men for a friendly poker night, but the mood is murderous. Chase gets abused by everyone. It's Brooke's turn to be bullied by Julian's bossy ma who pushes for a traditional wedding at a brides fair, where Haley - blaming pregnancy hormones - sides with the enemy every time.

Clay finally gets some hand muscle control back. As he predicted, Nathan had no reason to be gloomy about his first contract, football talent Troy, which is signed to all parties' satisfaction. Julian and Brooke stand up to his mother, who has to back down on the fancy wedding plans but relapses into drinking. After some occupational therapy for Mouth and himself, Chase handles his Alex-Mia-dilemma. In Nathan's absence, Jamie finds it even harder to face the peril of peer ridicule for getting braces, which Haley only compounds by wearing a 'commiserative' eye-patch.

The gang gathers at Nathan and Haley's to spend Thanksgiving with friends and family.

Nathan goes back to college and opts to take a harder class but he doesn't get a very welcome reception from his college professor and so with Jamie's help they figure out a way for Nathan to do better at college. Haley and Mia book Erin as warm-up act to Kid Cudi at Tric with both Mia and Alex acting as competing bar staff. Elsewhere, Quinn looks up Dan Scott and enlists his help to kill Katie Ryan but he manages to talk her out of it but she may regret her decision as Katie heads back to Tree Hill. Julian finds a list belonging to Brooke of things she's always wanted to do but never got around to so he sets about making them all come through so that she gets her lost inspiration back.

The biggest day of Brooke Davis' life has arrived, her wedding day. Julian gets his parents to agree to a truce on their special day, but will they uphold their end? Brooke makes up with her mom, and when her dad fails to turn up, her mom walks her down the aisle. Nathan's advice of sincerity helps inspire Julian's 'best man' Jamie to make a brilliantly simple speech. Chase disagrees with Skills' absurd security-obsessed job description for them as ushers. He ends up making hotter use of the limousine.

Brooke, Quinn and Haley decide to use their talents for the greater good. Meanwhile, Julian takes on a directing job and helps out a friend, and Chase mentors Chuck.

Sex games, secrets and shoelaces all come into play as the couples of Tree Hill celebrate Valentine's Day.

As the girls plan a surprise baby shower for Haley, the guys participate in try-outs for Jamie's baseball team. Meanwhile, Brooke and Julian pursue adoption, while Mouth gets Millicent ready for her first day at work.

As Haley's due date approaches, she takes steps to ensure that all her friends and family will be ready when the time comes. Brooke and Julian also prepare to begin a family, while Chuck turns to Chase for help with a problem.

The big day has finally arrived and the gang gathers at the hospital to await the birth of Haley and Nathan's baby. While they wait, they reminisce about the memories they have shared over the years.

While Haley stays at home to take care of the new baby, Quinn organizes a concert at Tric. Meanwhile, Brooke gets an offer to return to Clothes Over Bros, and Nathan sets his sights on exposing Professor Kellerman.

As Nathan, Julian and Clay coach Jamie's first little league game, the situation regarding the accident comes to a head. Meanwhile, Chase asks Alex to take a drug test for him, and Quinn gets an offer to shoot in Puerto Rico.

Nathan, Jamie, Clay, Julian, Chase and Chuck have a camp-out on the Rivercourt. Meanwhile, Brooke, Quinn, Alex and Lauren take a trip to Puerto Rico.

Haley and Brooke get ready to re-open Karen's Café as Brooke's pregnancy progresses. At her scan she discovers that she is expecting twins. Nathan and Clay set off on the road to scout new talent and it forces Nathan to finally go and see Dan. Chase leaves for the Air Force leaving behind two disappointed people - Chuck and Alex. Meanwhile, Mouth and Millie start their new morning show together but Millie is wooed away to start a new show with another co-anchor in Charlotte.

Before tired Nathan can finally rejoin his longing family, Dan has turned up and secured himself a temporary stay on account of his burnt-down restaurant, where he lived, but may have torched it. Chase is happy but exhausted on account of running the bar and an intense sex life with Alex. As if nocturnal baby care exhaustion wasn't bad enough for Julian and Brooke, his studio project only seems to bring debt and her boys fashion label fails to get financed, but her father Ted Davis actually turns up for the twins' christening. Clay's exhaustion is diagnosed medically serious. Chris Keller got engaged by Haley's music label under an alias, immediately antagonizes Alex but proves himself an genius producer.

Chase confides only in Chuck his plan to move Alex's things into his place. They ignore Chris Keller made her an offer for a career-boosting, national tour. As even the psychiatrist Clayton grudgingly consults can't properly diagnose his problems, Nathan decides with support from Jamie and Haley to attend in his pace the European forum for international sports talent scouting. This allows Dan to prolong his stay and carry out a mysterious plan. Julian warns Brooke that Victoria tries trough him to sabotage her father's apparently business-wise sound project to co-found a male fashion label.

Chase is heartbroken after Alex's desertion to take the tour Chris Keller advised, yet overcomes his bitterness toward Keller, who pleads her artist temperament was a lost case from the start. Julian is near despair about the unused studio until a TV series project comes within reach. Alas coaxing the studio proves tragically incompatible with paternal duties, while Brooke charms investors for her boys fashion project with her father. Clayton's problem is worse then thought, as Quinn discovers spying on him. Haley now runs Karen's café, but her cook is sick, so Dan steps in but that costs some bigot customers, and a mystery competitor opens across the street.

Julian is even more shattered than Brooke, who gives him the silent treatment, over having forgotten baby son Davis in his car. Although the boy is alright, Brooke leaves with the twins until Haley talks sense into her. Drunk, Chase enjoyed a wild night with a shameless flirtster but shyly wriggles out of continuation in the morning, on account of Alex's memory, only to find her with Chris Keller the next day. Dan and Jamie enjoy camping but dreaded Nathan's return is likely to mean grandpa's exit. After Dan scares away Clay's dealer, he comes clean to Quinn and consults Dr. Alvarez, who promises recovery but only after residential therapy.

Chase bravely bares Chuck's absurd, imitative adoration for 'cool', actually neglectful Chris Keller and stands by the ingrate knave when his father Wade Scolnic finally visits, but discards Chase as if a random babysitter. Nathan is missing since his flight home from Europe days ago. After cocky Keller helps activating Tree Hill PD officer Stevens, Haley finds Dan's cash stash and suspects a horrible crime. Julian can't forgive himself even now his loved-ones do, blames himself for bullying by strangers and picks a bar-brawl to get a 'bloody good' beating. Pushed by Dan and Quinn, Clay checks in for residential therapy with Dr. Alvarez, keeps dismissing 'mere talk' as therapy, but decides against signing out after meeting shy Logan, a neglected orphan boy who hangs around the rehab clinic.

Dan enlists Julian to help in his search for Nathan. Mouth fills Clay in about Nathan, as Haley explains Nathan's disappearance to Jamie. Brooke gets an idea of how to bring patrons to an empty Karen's Café, and Chris Keller confronts Chase about Tara.

Haley seeks help from Lucas as Nathan makes an escape attempt. Brooke comes face-to-face with Xavier. Julian uncovers evidence that assists Dan in his search for Nathan. Clay makes a connection with another patient.

Haley receives news of a possible tragedy. Dan's search for Nathan leads him back to his dark past. Clay has a breakthrough in his treatment. Brooke and Julian deal with Xavier. Chase's concern for Chuck pushes him to his limits.

Brooke and Julian take new measures to protect their family. Skills helps Mouth get to a turning point, and Chase faces consequences for defending Chuck. Clay reaches a new understanding with Logan.

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

Nathan's practically safe return causes general joy. The only downside is Dan's condition, probably terminal, but the whole family is in a forgiving mood while reminiscing, only Lucas refuses to come. Julian is welcomed as a hero and hears Brooke survived Xavier's attack, then stands by her as a paternal visit proves too good to be truly non-business. Clay goes to Sara's parents, who have raised Logan, and gets them to agree to let his son be invited home with him and Quinn.

Julian finally sells his One Tree Hill series concept to a studio and is hired to complete the script. Clayton and Quinn, who welcomes Sara's memory to, patiently win Logan's trust to become a warm; close family. Chase gets over his confidence crisis as bar manager just before he's offered a chance to buy Tric from Karen on the boat burning day. After Julian scolds father-in-law a useless father and Brooke 'surprises' her divorced parents back in bed, an unexpected business move makes up for a lot.

In the final chapter of One Tree Hill, the tenth anniversary of Tric brings old faces and new possibilities for the Tree Hill family. To celebrate the 10th anniversary they host a concert at Tric that includes Gavin Degraw. Julian buys Brooke's childhood home for them to live in. Nathan and Haley celebrate their 10th wedding anniversary.

Haley receives news of a possible tragedy. Dan's search for Nathan leads him back to his dark past. Clay has a breakthrough in his treatment. Brooke and Julian deal with Xavier. Chase's concern for Chuck pushes him to his limits.

Nathan, Jamie, Clay, Julian, Chase and Chuck have a camp-out on the Rivercourt. Meanwhile, Brooke, Quinn, Alex and Lauren take a trip to Puerto Rico.

Chase confides only in Chuck his plan to move Alex's things into his place. They ignore Chris Keller made her an offer for a career-boosting, national tour. As even the psychiatrist Clayton grudgingly consults can't properly diagnose his problems, Nathan decides with support from Jamie and Haley to attend in his pace the European forum for international sports talent scouting. This allows Dan to prolong his stay and carry out a mysterious plan. Julian warns Brooke that Victoria tries trough him to sabotage her father's apparently business-wise sound project to co-found a male fashion label.

Sex games, secrets and shoelaces all come into play as the couples of Tree Hill celebrate Valentine's Day.

As news of Peyton's condition spreads, Marvin and Millicent struggle to remain a couple and Brooke tries to suss out Julian's intentions. Peyton and Lucas babysit Jamie and his friend, while Haley and Nathan spend a night out together with Chase and Mia.

Brooke and Julian take new measures to protect their family. Skills helps Mouth get to a turning point, and Chase faces consequences for defending Chuck. Clay reaches a new understanding with Logan.

The gang gathers at Nathan and Haley's to spend Thanksgiving with friends and family.

Haley and Brooke get ready to re-open Karen's Café as Brooke's pregnancy progresses. At her scan she discovers that she is expecting twins. Nathan and Clay set off on the road to scout new talent and it forces Nathan to finally go and see Dan. Chase leaves for the Air Force leaving behind two disappointed people - Chuck and Alex. Meanwhile, Mouth and Millie start their new morning show together but Millie is wooed away to start a new show with another co-anchor in Charlotte.

Haley seeks help from Lucas as Nathan makes an escape attempt. Brooke comes face-to-face with Xavier. Julian uncovers evidence that assists Dan in his search for Nathan. Clay makes a connection with another patient.

With senior prom only weeks away, Haley's frustration over her injuries increases and Skills and Mouth hatch a plan to help Nathan earn money for the big dance by stripping. Brooke betrays Rachel in order to get closer to a new guy and Peyton and Lucas resolve to be happy. Struggling with her drug addiction, Deb makes a choice that could end her life.