Brooke looks for a model as the new face of Clothes Over Bros. Mia and Haley fall short of selling a million records. Dan finds a confidant in an unlikely person. Nathan deals with being distant from the ones he loves, while Clayton reminds him he's in the NBA. Tree Hill's former bad girl - Rachel Gatina returns.

Nathan and Haley have to decide what to do about Renee's pregnancy claims as Clay thinks paying her off is the best way as it is Nathan's contract year. Mouth is asked by his station manager to investigate any titillating scandal about Nathan but decides not to tell his boss about the alleged pregnancy. Mouth and Skills come to an agreement about living together and Alex tests the patience of Millicent during a photo-shoot. Later she gives Julian a film script. Meanwhile, Quinn's husband David comes to find her when she won't answer his calls.

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.

Victoria bails Millicent out of jail the morning after her arrest and tells her to get herself together before she shows herself again. But Victoria is doubtful that Millicent has learned her lesson and proceeds to keep an eye on her and she is proved correct when Millicent steals a dress from Brooke's new collection to give to her model friend Makenna is exchange for a packet of blow. Mouth is distraught at the change in Millicent and they break up. Clay tries in vain to hold onto his one client but it is not to be and so he packs up his apartment much to Quinn's dismay. Nathan is told by his agents that he won't play NBA this season and his only option is to play in Spain and be ready for the next season but this move coincides with Haley's planned record tour of the US. Skills records a video with the help of Jamie for a new job in L.A. Elsewhere, Julian mistakenly tells Alex that Brooke cannot have children which further deepens the rift between Brooke and Julian after Alex tries in her own way to help Brooke. Despondent after being told to stay away from Julian Alex slits her wrists in the bath and leaves Julian a voice-mail telling him she won't bother him anymore.

Clay gets his mojo back with some help from Quinn and which might mean that Nathan can stay in the US and play in the NBA with the his old team the Charlotte Bobcats instead of going to Spain. Skills gets offered and takes the job in Los Angeles and brings Mouth along for the ride. Dan goes against Rachel on his television show and tells his audience that this is his last show and also serves with divorce papers. Julian rescues Alex from her near suicide bid and tells her the film deal is back on. Brooke fires Millicent from her model contract and tells her to get immediate help for her drug problem but her stay in rehab is brief. Victoria hires a new designer, Alexander Coin, for the menswear collection without telling Brooke.

Nathan and Jamie join Haley on tour as it comes to a close. Quinn gets her divorce from David. Millicent appears in court for her DUI where Victoria offers her a job as her assistant at Clothes over Bros. Brooke finds it hard to trust Julian particularly when Alex is always by his side and ends up turning to new menswear designer Alexander Coin. Elsewhere, Haley and Quinn's sister Taylor turns up in Tree Hill with Quinn's ex-husband David who is now her boyfriend. Meanwhile, Mouth returns from L.A.

Nathan tries to calm Haley down after Taylor and David's shock announcement that they are a couple and then through the ensuing dinner that Taylor plans out until all three James sisters find themselves in the pool fighting it out. David and Quinn talk and he agrees with her that their marriage is at an end. Julian takes offense to the director hired for his new film and fires him after he punches him for insulting Alex. Finally after talking to Brooke rationally and asking her to be the movie's costume designer she makes him see that he should direct the movie himself which he brings up with his father who agrees. Mouth and Lauren fix up the disheveled apartment after Millicent's recent partying and then tells Millicent he is staying in Tree Hill. Millicent and Brooke agree to try and be friends again.

Flashback to the '80s.

Haley, Quinn and Taylor receive a surprise visit from their mom Lydia who tells them that she has incurable pancreatic cancer and that she is not seeking any further treatment. Quinn takes the news very hard but Clay is there to support her. Meanwhile, Alex sets her sights on Alexander as Brooke and Julian try to get their old relationship back on track, and Millicent finds herself struggling with temptation.

Haley and Quinn refuse to accept that their mom Lydia will not fight her pancreatic cancer and after some convincing manages to persuade her mother to get a second opinion with Nathan's doctor but the results don't bring any change. Because she told Jamie that she won't be alive for Christmas he organizes for her to have Christmas now with the family. Meanwhile, Brooke and Julian's relationship moves up a notch but comes crashing down spectacularly when Brooke finds Alex in his bed but is it what it seems? Elsewhere, Grubbs puts Miranda through hoops before he allows her to produce his album with her and Owen Morello comes back into Millie's life much to Mouth's displeasure.

In getting back at Julian for sleeping with Alex, Brooke messes with the costumes for the shoot and generally does her best to wound Julian but it takes comments from Alex to get her thrown off the set after she punches Alex in the face. Only later does she discover that it was Alexander that Alex slept with as she switched rooms with Julian. She tells Victoria who is furious and it later transpires that her mystery lover is Alexander. Meanwhile, Lydia takes ill from her cancer and is hospitalized and reaches out to the daughter Taylor but it is Quinn who manages to get her to come before she dies. Elsewhere, Clay tells Katie he won't be representing her but it doesn't put off Katie and she finds out that he was married to Sara so she transforms herself to look like her. Lauren and Mouth nearly get it together only for Skills to come back to Tree Hill.

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?

Nathan and Haley struggle with the aftermath of her mother's death, while Brooke deals with the fallout of Alexander's tryst with Victoria. Alex discovers a secret about her leading man, Josh, that could derail Julian's film, and Quinn is confronted by an unhinged Katie.

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 the situation at the hospital worsens; Nathan makes a huge decision regarding his career. Brooke and Julian take Jamie for the day, while Victoria and Millicent hatch a plan.

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.

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

After a wild night out on the town for her bachelorette party, Brooke and the girls try to piece together the night before amidst the wreckage of the day after.

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.

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.

After a wild night out on the town for her bachelorette party, Brooke and the girls try to piece together the night before amidst the wreckage of the day after.

Victoria bails Millicent out of jail the morning after her arrest and tells her to get herself together before she shows herself again. But Victoria is doubtful that Millicent has learned her lesson and proceeds to keep an eye on her and she is proved correct when Millicent steals a dress from Brooke's new collection to give to her model friend Makenna is exchange for a packet of blow. Mouth is distraught at the change in Millicent and they break up. Clay tries in vain to hold onto his one client but it is not to be and so he packs up his apartment much to Quinn's dismay. Nathan is told by his agents that he won't play NBA this season and his only option is to play in Spain and be ready for the next season but this move coincides with Haley's planned record tour of the US. Skills records a video with the help of Jamie for a new job in L.A. Elsewhere, Julian mistakenly tells Alex that Brooke cannot have children which further deepens the rift between Brooke and Julian after Alex tries in her own way to help Brooke. Despondent after being told to stay away from Julian Alex slits her wrists in the bath and leaves Julian a voice-mail telling him she won't bother him anymore.

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.

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 and Haley struggle with the aftermath of her mother's death, while Brooke deals with the fallout of Alexander's tryst with Victoria. Alex discovers a secret about her leading man, Josh, that could derail Julian's film, and Quinn is confronted by an unhinged Katie.

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.

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.

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

Nathan and Jamie join Haley on tour as it comes to a close. Quinn gets her divorce from David. Millicent appears in court for her DUI where Victoria offers her a job as her assistant at Clothes over Bros. Brooke finds it hard to trust Julian particularly when Alex is always by his side and ends up turning to new menswear designer Alexander Coin. Elsewhere, Haley and Quinn's sister Taylor turns up in Tree Hill with Quinn's ex-husband David who is now her boyfriend. Meanwhile, Mouth returns from L.A.