After Lucas and Keith learn that Dan had a heart attack and is still in the hospital, they decide it is best for them to return to Tree Hill. When Deb learns about Haley and Nathan's marriage, she grows hostile. Meanwhile, angry that Lucas left Tree Hill without saying goodbye, Peyton and Brooke try to mend their friendship.

With the assistance of Peyton and Brooke, Lucas throws Nathan and Haley a wedding reception. Although Haley's parents support Nathan and Haley's 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.

Although Nathan and Haley are already married, Tim insists on throwing Nathan a post-wedding bachelor party, while Brooke throws Haley a bachelorette party. Meanwhile, Lucas tries to decide whether he should visit Dan in the hospital. Karen decides to go back to school and Nathan gets a job working for Keith at Dan's dealership.

Brooke tells the Latino pool boy he's not allowed to use the swimming pool, and when he gets out finds he was skinny diving- the next morning he turns up at her school in a sports car; it's her new neighbor Felix Taggaro, who is even more flirtatious, self-confident and sassy then she and uses Mouth to find his way. At college Karen gets to know personally her business economics professor Andy Hargrove, a retired self-made tycoon. When Lucas tells he wants to use Dan's rehabilitation to get to know him properly, Nathan gives him his blessing. Dan orders Keith to fire Nathan, to no avail. When Keith advises against the second hand car Haley and he hoped to buy, he generously spends the money on a keyboard so she can work on her composing talent- and gets barked at to take it back by his ingrate wife. Peyton gets a chance to manage a famous musical duo, but only if she supplies them with and uses cocaine. While taking a sports car for a test-spin, Dan makes Lucas accept Felix' race dare, and offers him the keys- which chases him away. Deb encourages Karen finally to start her long-dreamed bar extension to the café and is asked to help run it as a club. Now she's poor, Brooke is caught shoplifting but Felix saves her bacon. Keith offers Nathan to learn car mechanics by fixing together a car/wreck he intended to strip for parts, which Nathan may then keep.

Felix organizes a "dare night" to test the limits of his new classmates. While out playing the game, Lucas meets a mysterious new girl, Anna. Peyton tearfully confesses to the church that she recently tried cocaine and Keith is caught off guard when a beautiful woman comes to the shop and begins flirting with him. Meanwhile, Karen goes on a date with Andy, her younger professor.

Peyton meets cocky record shop clerk Chris Keller who turns out the only good musician on the club's auditions besides Haley, who has too much stage-fright. Coach won't listen when Lucas genuinely suggests to reconsider an eye operation. Lucas learns Anna is overprotective Felix' sister. Nathan gets a once in a lifetime invitation for the three months Highfliers basketball summer-camp in Florida. Now her parents are financially ruined, Brooke decides to recruit Felix as her purely physical toy-boy, and is forced to hold a garage sale. Dan invites Deb to watch the meteor shower together, Andy asks Karen, Anna gets Lucas to. Keith has a romantic date with his car-naive lady-client Jules. Nathan pretends to Haley not be accepted for Highfliers fearing they can't afford it and makes her overcome her stage-fright. When Dan realizes Deb is not ready for reconciliation, he pretends his actually excellent rehab-results are bad. Mouth proves his love for Brooke by buying back the doll-house she failed to overprice enough.

Felix continues to be Brooke's sex-toy. Chris makes Peyton beg for him to perform at the Tric club opening and hands her a 'rider' (list of demands), which inspires Brooke- about non-committal rules for Felix. Dan tells startled Karen he forgave Keith for sleeping with Deb, news to her. Keith asks Jules to the opening, they become exclusive. Coach, in hospital, understands Nathan gives up Highflyers for Haley's sake; seeing the crowd gives her major stage-fright, but when Chris leaves the stage because the teenage crowd won't listen quietly she plays, to applause, then he invites her to collaborate musically. Mouth hoped to get a shot at Brooke, but she commends him as a- sweet little brother, ouch; he accuses Felix, Lucas gets it backward and catches a solid punch, mainly for dating Theresa; Craig throws Felix out, Mouth brings drunk Brooke home, who only wakes up when Felix is beside her.

Brooke, Peyton, Haley and Anna have a slumber party at Haley's apartment where secrets and lies are revealed. Meanwhile, when Lucas and Nathan go on a road trip to a Bobcats game, Nathan reveals he is being tested for the genetic defect that caused Dan's heart attack and suggests Lucas do the same. After an awkward encounter with Keith and Jules, Karen and Andy share an intimate night together.

Haley makes Nathan agree to go to the prom even though his parents will be chaperons; Peyton pays Brooke's chosen dress for it; Lucas tells Felix he's taking Anna; Mouth comes alone 'on the prowl'. Lucas learns Dan is hiding his full recovery. Haley finally accepts to play with Chris in Peyton's club, but they run late, leaving Nathan dancing with his ma; when she finally arrives they are crowned king and queen of the ball but just then Nathan learns she worked with Chris even while he was in Charlotte, and ends up showing he gave up Highflyers for her. After Mouth tells her he, not Felix, took care of her while she was drunk, she's livid and tells Felix he'll never have her heart.

After the prom, Anna sleeps over at Peyton's- Felix sneers she's getting a worse reputation then his, while Peyton has a hard time with lesbianism-innuendos, even though Brooke says that appeals to boys, but ends up making a stand at school. Brooke finds Nathan slept on Lucas's floor; when he goes home, Haley tells him she respects his sacrifice and wants him to go to Highflyers, but won't do the one thing he asks, stop seeing Chris, so he walks out again and warns Chris in ominous terms and grip. Brooke blames Felix for her broken windshield and rages at him; he finds out it was Mouth, who also tells Lucas, but pays anyway; in the end he convinces her of his love. Dan takes the reins back at the dealership and offers Keith to stay on. Karen orders Lucas to take the medical test, or no basketball anyway- Nathan confesses he told her. Chris gets a chance to make a tour, asks Haley along and kisses her again. After Deb confesses her infidelity with him to Karen, Jules gets a call from Keith he loves her, and reports it to Dan

After Deb's confession to have slept with Keith, Karen shows her the door and later has a misunderstanding which makes her break up with Andy. Haley chickens out on her music career at the last minute, so Chris leaves alone. When she gets home, her older sister Taylor is there. Nathan hopes she won't remember she was his first sex partner at a party in the beach house. They become friends and he decides she can stay a few weeks. Jake is back, without Jenny, for a few days he spends mainly with Peyton. Lucas finds out how Jules' poverty drove her to break Keith's heart. Felix has a fight with Lucas for 'hurting Anna' -who later confesses to Lucas she's just lesbian but hoped to be bi. Karen and Andy ultimately make up.

Karen decides to make Lucas's life as miserable as possible till he takes the heart test and asks Andy over while his house is in a contractor's hands. Brooke needs a job- the Crab shack hires her, but not as waitress, just 'PR' in a crab suit; she quickly makes friends with the other underpaid girls but is the only one to develop a militant labor union attitude. Lucas confronts Dan about Jules, and is told about Debs adultery with Keith, who cannot deny it and swears Jules is his true love. Taylor sees Haley's tattoo and bugs her and Nathan about not following big sister's own advice in the past; when Nathan warns her to stop hinting at their first night she bitches back the full truth can hurt him more- so he tells Haley himself, who needs a cooling off period but then understands it was before they knew each-other; all three make up. Lucas confides about Jules to Anna, now he knows her lesbian secret. Keith offers Luke to take the HCM-test together, now Jules wants him to. Dan hosts and even cooks for a dinner with Keith and Jules, constantly getting at their and Deb's nerves, and afterward warns her Keith won't forgive her if he tells him their dirty secret; Keith tells Lucas Jules just accepted his wedding proposal. After researching regulations, Brooke starts hard action- they are all fired, and threaten to tell the public about his inferior crab supplies, and get a raise, but quits anyhow and turns her attention to Felix and running for student council president. Karen gives up forcing Lucas- and hears he just took the test.

Brooke plans her presidential campaign with Felix; her opponent is confident, never-defeated Erica Marsh, who lives for the job. Dan asks Lucas to move in with him while offering Keith to pay for a grand wedding with Jules. Nathan discovers lovers e-mail to Chris from Haley on their computer, believes her most are from Taylor and they decide the stirring sister must leave. Jake is back for good, moves in with Peyton and asks coach for a good word at school. Erika plays the campaign dirty, so Brooke decides to pull all the stops and asks Lucas to write her a killer speech- he suggest a J.F. Kennedy address. At the club Tric, Chris Keller is back, as artist opening act; he also dares Nathan about Haleys love, and once the main act 'the Wreckers' has asked him along on their tour invites Haley to join them- she tells Nathan she wants to, solely as a unique career opportunity, and is told to choose: the tour or him, and yet she goes. Karen fails to stop Lucas moving to Dan or at least find out why: he will pay for Lucas' medication, as he was not tested negative but showed her Keiths results.

Deb is angry to hear from Dan Lucas moves in, but hopeful now Haley has left Nathan he might also return. Nathan is a wreck, and seems determined to wreck his school-prospects; he won't listen to anyone, even hits the still taunting Dan. Jake and Jenny live in Peyton's room, but she is reluctant to become intimate again. Erica stops at nothing to defeat Brooke, but clever speeches by her and Mouth still turn the tide. Lucas seems to feel at home with Dan.

Coach tells the students of Tree Hill High to make a video recording for the traditional time capsule they expect to be open in 50 years. When Mouth tells it's sometimes opened early, Anna convinces him to help erase hers- they can't resist watching some other. Lucas moves in with Dan; Andy helps Karen to fight Dan in court, but she fails to remain rational. Nathan continues his self-destruction, believing Haley will never return, quits his job at Dans garage and gets Lucas and him arrested; they fight over Dan and Keith so Lucas tells his true motivation, and Dan understands when Nathan tells when he bails them out. Peyton and Jake go on their first date. Brook starts to really think about what she can do as president. When Jules tells Dan she'll tell Keith the truth, he says he may just keep off anyway. Jake and Peyton are becoming comfortable with intimacy.

Brooke is high: she's about to be installed as school president and her dad should get another well-paid job. Nathan, still drinking, is livid after a call from Haley she'll be on TV, refuses to go to Keiths wedding, gets no sympathy from coach -who even rats out his fake ID in the liquor store- and drives Deb to abuse pain killers, as Lucas soon finds out. Andy thinks Karen can get Lucas back now his detective found Dan pays all expenses for some Emily Chambers. Chris makes it appear on national TV as if he and Haley are a couple. Best man Lucas takes Brooke, Jake and Peyton are late as they are too horny, Nathan turns up drunk and cursing outside the church. When Andy learns Jules is Emily, Karen asks and guesses what Dan pays her for- Jules runs off, only Dan triumphs. While Nathan burns his memories of Haley, Deb tells him to go get her back. Brookes dad got the job- but must move to California next week...

Niki turns up with a court decision in absentia awarding her custody of Jenny- Andy offers Jake legal help as fleeing is losing. Lucas goes to his ma now the truth is out but decides to stay with Dan as he considers himself the enemy's only weak spot. Keith feels betrayed by everyone; Dan can't resist gloriously admitting having set him up and is physically assaulted. Brooke dreads her impeding departure and realizes she may stay with a friend; Peyton is willing, but her parents refuse. Anna turns Felix in to the principal for writing dike on Peyton's locker, with disastrous results: he is dumped by Brooke, his parents send him to military school, and Anna even blames him for not knowing she's the lesbian. Nathan drives to where Haley tours, pours out his heart ready to do everything for their marriage, but only hears she wasn't ready and right now the show comes first, so he returns. Lucas makes Brookes year: Karen and he take her in. Keith leaves, anywhere and maybe forever.

Lucas and Peyton hide Jake and Jenny at Nathan's place while he chases Haley. Lucas finds Dan's secret hiding place for cash and a secret ledger; when he and Andy come to get it at night, all is gone. Anna's former lover Darby turns up; she ends up coming clean to her parents, who still love her, but returns to boarding school. Nathan accepts an invitation to spend the night at the bar where Taylor works; they drink heavily and participate in the bar dancing show. Niki claims Jenny isn't Jake's biologically. Brooke stays late at a party without permission, misses her shift in the café, and learns to pay her debts and her dues chore-wise. Jake won't hear reason from his lawyer and chooses jail over handing over Jenny to irresponsible Niki, even if that's his best chance to get her back in a few months.

Deb's cool younger brother, race pilot Cooper 'Coop' Lee, visits his favorite nephew Nathan and invites him and Lucas to Lowe's Motor Speedway (now Charlotte Motor Speedway), where the boys and his kid brother Jarret get a crash course from competitor Ray Green's daughter Daytona 'Toni' in not crashing for a taste of the race. Dan informs college about Andy's improper relationship with Karen- he must choose and gives his notice. Mouth fakes being drunk so Brooke can 'drive him home'; Erica is a real client, and hits on with him, kissing. Dan finds Deb wasted in the garden. At the day of the (private) race, competitive athlete Nathan's pride is hurt, so he tries to break the track speed record but crashes with bad long injury; the doctors tell Deb her blood is too 'rich' in pills to donate; Toni thinks Nathan was suicidal. Coach tells Peyton Jenny is safe in a small Florida town.

While Nathan is unconscious in the hospital, he dreams a nightmare alternative version of his life, in which Dan married Karen and lives with her and Lucas, while Keith is the successful car dealer, Dan is assistant coach and trains Lucas as the Ravens star. Nathan is the poor underdog living with Deb -who runs the café- but may still be recommended for Highflyers by coach Whitey if he wins a duel; Haley is his girlfriend, Brooke makes a pass at him. Karen cheats on Dan with Keith. Peyton goes steady with Lucas but tells Haley to warn Nathan about Lucas' dirty plans; Dan's attempt to bribe Nathan off actually motivates him to fight, so he is abducted, bound and dumped by Lucas's Ravens hardcore. Peyton dumps Lucas, who loses the duel after she picked Nathan up.

Nathan is recovering and back home, but won't tell Lucas what drove him. Brooke pieced together a shredded invoice Lucas sneaked home, so she learns about his investigation for Dans car dealership scam, and Andy makes sense of it but feels Lucas should stop taking risks. Nathan was relieved to hear his hospital bills are all paid, when Dan bursts in; he refuses to move back home even during revalidation, but keeps annulment forms. The kids planned a benefit film night for Nathan's medical bills, and go on just for the fun; to their surprise he appreciates an accidental films switch showing car accidents. After talking to Peyton he wants to forgive his ma for fleeing into pills, as she begs in a letter, but understands his insurance wasn't paid, so he sees Dan who confirms he paid, the rent too, and ends up believing he could be on the road to becoming a bitter bastard like him if he makes the wrong choices; he even asks Lucas to back off his investigation and decides to return home; Haley got her annulment petition offered by Dan too. Andy shows Lucas the profits went largely in a college fund for him; he moves back to Karen when Nathan returns.

The class's last essay assignment is about what they lost during the year, which sets some thinking. Karen attacks Dan when she learns he tries to get Andy deported; Andy cleverly trick him to check the black books hiding place. Jake has high hopes to get Jenny back now his attorney found Nikki lied under oath about attending college; but the day before, Nikki visits him to show she found Jenny already... Coach encourages Nathan to go to Highflyers, as he has grown in character enough, but Dan claims his ma Deb will collapse again if he leaves after her return. Karens club TRIC fills for Jimmy Eat World. Lucas and Brooke visit New York for an overnight stay with Haley; Chris says they never had sex, but she refuses to give up her musical life. Jake tells Peyton to forget him as his quest for Jenny looks desperate.

Lucas and Brooke's relationship becomes more intimate when they travel to New York for an overnight stay with Haley.