An accusation threatens Nathan's NBA career, much to the chagrin of his sports agent Clay. Brooke prepares to launch a new fashion line, and Julian decides to produce a big movie. Haley's older sister Quinn makes a surprise visit. Mouth wants Skills to move out, though Skills refuses which leads to a naked standoff. Meanwhile, Jamie celebrates his 7th birthday.

Since Peyton has been gone for a year, Haley has to do everything in her power to protect Red Room records with the help of Mia as they make her new album. Brooke casts the new face of her clothing line, though her personality turns out to be what Brooke hadn't expected. Clay defends Nathan against a growing scandal. Julian and Brooke decide to move in together. Julian's father visits. Meanwhile, Dan unveils his new bride, Rachel Gatina.

Clay and Nathan disagree on how to handle an ever-worsening scandal. Quinn and Brooke organize a photo shoot, and Mouth ups the stakes in his battle with Skills. Meanwhile, Alex makes Julian an interesting proposition.

Nathan's scandal becomes public. Brooke's fashion show brings an unexpected responsibility for Millicent, and Haley convinces Quinn to talk to her estranged husband David. Meanwhile, Mouth makes a decision that could threaten his career. At Brooke's fashion show, Clay gets into a fist fight with Quinn's husband.

Haley is thrust into the spotlight and storm of Nathan's growing scandal. Against her better judgment, Brooke allows Julian to continue working with Alex. Millicent gets a new job, which may cause trouble for Mouth. Meanwhile, Clay and Quinn grow closer.

While Haley begins to wonder if Renee's accusations have merit, Nathan's scandal threatens his endorsement deals and so Haley considers taking matters into her own hands. Julian gives Alex another chance, and a jealous Brooke reconnects with Chase. Millicent questions whether she has what it takes to be a model. Meanwhile, Clay lets Quinn in on a big secret.

Nathan and Haley are dealing with the fact that Dan has invited Renee onto his show, where she will undoubtedly air out the young Scott's dirty laundry. Quinn contemplates where her marriage with David went wrong, while Brooke has to admit to Julian what her future plans and dreams are. Clay must deal with his past when Sara comes to town.

Julian agrees to a weekend camping trip but struggles to fit in with Nathan and the guys. Back in Tree Hill, Brooke and Haley spend Girl's Night doing a little bonding of their own, and Quinn helps Clay come to terms with a tragic loss. Meanwhile, Dan and Rachel's past catches up to them.

Haley returns to the stage and Brooke receives life-changing news. Meanwhile, Dan Scott returns to Tree Hill much to the chagrin of Nathan, who is about to sign a new NBA contract with the help of his agent Clay. Quinn and Clay grow closer.

Nathan reaches the breaking point with Clay, causing a rift between Haley and Quinn. Brooke comes clean with Julian about her worries regarding his growing connection to Alex. Meanwhile, Skills pursues a new career in LA and Millicent's drug problem worsens.

Nathan and Haley's careers bring about a tough decision for the family, and Julian divulges a secret to Alex that leads to a confrontation with Brooke. Meanwhile, Clay tries to resuscitate his career as an agent, and Jamie learns the truth about Skills' new job. And a fresh-from-jail Millie finds an unlikely supporter in Victoria. After a shocking conversation with Julian, Alex leaves her suicide note on his voice mail.

Quinn helps Clay form a plan to convince Nathan to rehire him, but they may be too late as Nathan and Haley prepare to leave Tree Hill behind in their move to Barcelona. Brooke struggles to accept Julian's reaction when Alex undergoes another crisis. Meanwhile, Millie's downward spiral threatens her relationship with Mouth, and Dan makes an announcement that shocks Rachel and his studio audience.

Three months have passed since the events of the Fall Finale, Haley, Nathan and Jamie return from tour, but are in for a shock when Taylor (Haley and Quinn's oldest sister) returns, and she brings a familiar face with her. Millie goes in front of the judge for her DUI. Scenes from Haley's concerts are also featured.

Nathan tries to keep Haley calm after Taylor shows up at their house with Quinn's ex-husband in town. Julian sticks up for Alex on the set of their movie, and Brooke leans on Alexander to ease her heartache. Meanwhile, Clay gets a chance to prove his commitment to Quinn by helping her through a dinner with her sister and David.

In the chaos surrounding an '80s alumni dance at the high school, Haley's birthday is forgotten, Jamie is left home alone, and Nathan and Clay are stranded 200 miles from Tree Hill. Meanwhile, Brooke's appearance at the dance with Alexander forces Julian to relive his dorky adolescence in an episode dedicated to the memory of John Hughes.

Haley, Quinn and Taylor receive life-changing news when their widowed mom, Lydia shows up to town. Brooke and Julian try to find a balance between their personal lives and work as the movie shoot begins. Alex sets her sights on Alexander, and Millicent finds herself struggling with temptation.

Nathan tries to help Haley and Jamie confront Lydia's seemingly hopeless situation, while Brooke and Julian navigate their volatile relationship in the midst of a hectic movie shoot. Meanwhile, Clay and Quinn spend some time apart, and Miranda tries to prove to Grubbs that she's the right person to produce his album. Owen returns to help Millicent with a recent problem.

As Brooke angrily deals with Alex's tryst with Julian, Lydia's condition worsens, prompting Quinn and Haley to try to reconnect with Taylor. Clay is forced to deal with Katie's unsettling advances, and Nathan helps Jamie come to terms with Lydia's impending death.

On the eve of Quinn's big gallery opening, an uninvited guest ambushes Clay. Nathan spends the day with Jamie, while Haley struggles with life after her mother's death. Brooke and Julian each receive a shocking surprise. Meanwhile, Skills learns the truth about Lauren and Mouth.

Haley struggle THE hardest 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 Clay is confronted by an unhinged Katie.

Nathan struggles to reach an increasingly depressed Haley, while Quinn leads Jamie on a Tree Hill treasure hunt. Julian shows his finished film to Brooke, and Clay is forced to deal with Katie.

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. Julian's film is a huge hit, Haley discovers some good news, Julian takes a huge step in his relationship with Brooke, and someone returns and does something that make sure Clay is single forever.