It's been four years since the gang left Tree Hill, and many things have changed. Lucas (series star CHAD MURRAY) has published his first novel, "An Unkindness of Ravens," and now works on his second. Along with Skills (series star ANTWON TANNER), Lucas also coaches his former high school basketball team, vowing to take the squad to another championship. Peyton (series star HILARIE BURTON), who is at the beginning of a budding music venture, loved two things when she graduated from high school: Lucas and music. But did leaving Tree Hill for an internship at a record company in Los Angeles change her mind about either passion? Peyton's best friend Brooke (series star SOPHIA BUSH) has been chasing her dream of becoming a top fashion designer with her clothing line Clothes over Bros. Four years later, Brooke finds herself at a crossroads; she has found some success, but at what cost? Nathan (series star JAMES LAFFERTY) and Haley (series star BETHANY JOY GALEOTTI), young parents who are trying to find their way, have also endured highs and lows -- particularly those of Nathan's career path -- but they have balanced this journey with the joys of parenthood as they raise their young son, Jamie (recurring guest star JACKSON BRUNDAGE - "Las Vegas," "Einstein Pals," "Lime Salted Love"). Enduring his own struggles, Mouth (series star LEE NORRIS) continues to chase a career in broadcasting but is finding the on-air business to be cutthroat and difficult.

Tensions run high as Lucas must face his past and choose his future, all while discovering the demands of coaching the Tree Hill Ravens. Haley makes the decision to hire a nanny (guest star TORREY DeVITTO - "Beautiful People"), which will bring much-needed help into their home. Plus, Haley's first day of teaching turns out differently from what she expected. Meanwhile, Jamie (recurring guest star JACKSON BRUNDAGE) sets his sights on a Soap Box derby race and enlists Skills to help him out. And Mouth's excitement about his new job is tempered by his demanding new boss.

Lucas's editor (guest star MICHAELA McMANUS - "The Beautiful Lie") wonders about Lucas and the timing of his recent creative inspiration. Brooke and Peyton make business plans, while Mouth tries to win points with his boss, Alice (guest star KELLY COLLINS LINTZ - "Surface"). Meanwhile, Lucas and Skills finally make some headway with the Ravens, and Nathan tries to wrestle free from the legacy left by Dan (former series star PAUL JOHANSSON). Plus, KEVIN FEDERLINE ("CSI: Crime Scene Investigation," "Britney and Kevin: Chaotic") guest stars as a problematic musician.

While Brooke makes plans for Clothes over Bros, Peyton finds she has her hands full when the musician (recurring guest star KEVIN FEDERLINE) she just signed turns out to be problematic. Meanwhile, Haley's own interest in music leads her back to the recording studio. Nathan tries unsuccessfully to corral a defiant player, Quentin (recurring guest star ROBBIE JONES), and Mouth's relationship with his boss grows heated.

In an episode set three years in the past, Lucas visits Peyton in Los Angeles with an offer that will change their relationship forever. Under pressure from Victoria (recurring guest star DAPHNE ZUNIGA - "Melrose Place"), Brooke must make a difficult decision about the future of her clothing line. Whitey (former series star BARRY CORBIN) is concerned when Nathan's temper flares on the night of the college basketball championship. And Haley struggles to balance the pressures of school and being a new mom.

Confrontations abound in Tree Hill. Lucas confronts Peyton about her harsh treatment of his editor, Lindsey (recurring guest star MICHAELA McMANUS), and Brooke intervenes when Victoria (recurring guest star DAPHNE ZUNIGA) meddles with Peyton's record label. Meanwhile, Nathan grows closer to Jamie's (recurring guest star JACKSON BRUNDAGE) live-in nanny, Carrie (recurring guest star TORREY DeVITTO), and Haley is challenged by her difficult student Quentin (recurring guest star ROBBIE JONES). Plus, Mouth is torn between loyalty to his coworkers and his illicit affair with his boss, Alice (recurring guest star KELLY COLLINS LINTZ).

It's a Tree Hill reunion as the entire gang gathers at Tric to see musical group The Honorary Title perform. Peyton and Haley see this as an opportunity to introduce their musical act; Carrie (recurring guest star TORREY DeVITTO) sees it as her chance to get closer to Nathan. Meanwhile, Brooke forces an unsuspecting Mouth to go on a blind date with Millicent (recurring guest star LISA GOLDSTEIN). And Lindsey (recurring guest star MICHAELA McMANUS) confronts Lucas about sneaking off to see Peyton.

While Haley wrestles with whether or not to reveal information that could ruin Lucas' relationship, Peyton admits her true feelings to Lucas. Brooke makes a play for Owen (recurring guest star JOE MANGANIELLO - "ER," "American Heiress," "How I Met Your Mother," "Spider-Man 3"). Mouth tries to convince Millicent (recurring guest star LISA GOLDSTEIN) that he's a better man than she thinks he is. Nathan is put in a position that could spell the end of his marriage. And, to add to the drama, Lucas and Skills face the coaching prospect of playing their season opener at a disadvantage.

At the first Ravens basketball game of the season, Haley, Brooke, Peyton, Lindsey (recurring guest star MICHAELA McMANUS) and Mia (recurring guest star, musician KATE VOEGELE) find themselves locked in the Tree Hill High library. Tensions run high as Peyton and Lindsey face off over Lucas, and Brooke tries to stand up for her mother when her friends go on the attack. Plus, Haley plays mentor to Mia, who is experiencing the elation and disappointment of fame. Meanwhile, Mouth, who is covering the game as his first official TV reporting assignment, struggles to find a story. And Lucas and Nathan grapple with whether or not to tell their loved ones about various indiscretions.