Nathan Scott (James Lafferty, Emeril) had the perfect life thanks to all the perks his rich dad's money could by. He had the girl, the car and the star position on the high school basketball team. On the other side of town, his half-brother, Lucas Scott (Chad Michael Murray, Dawson's Creek, Gilmore Girls), an intense loner, who had been ignored by Nathan's father since birth, had a different story to tell. Their lives were taking separate paths until the day Lucas was asked to join the basketball team.

Now, the half-brothers are battling it out for control of the court and for the hearts of the three young women who are fast becoming an intricate part of both their worlds. At the center of their greatest conflict is Nathan's high school sweetheart, Peyton (Hilarie Burton, MTV's TRL), a tortured yet gifted girl, who keeps most of her true feelings hidden from the world. Much to Nathan's dismay, Peyton and Lucas soon discover they have a bond that can't be broken.

While Peyton and Lucas face the consequences of their feelings for each other, Nathan's attraction to Lucas' best friend Haley (Bethany Joy Lenz, Guiding Light), an unusual and intriguing girl who doesn't have a clue about the world of wealth and privilege, takes center court.

Meanwhile, Peyton's wild and outrageous best friend, Brooke (Sophia Bush, Van Wilder), seems hell-bent on partying and sleeping her way through high school, Lucas included.

While the five teens struggle to find their places in the world, the adults in Tree Hill are dealing with the consequences of decisions made years ago. Nathan's father Dan (Paul Johansson, John Q) and Lucas' mother Karen (Moira Kelly, The West Wing) were high school sweethearts. When Karen became pregnant during their senior year, she was devastated by Dan's decision to put his own life and career first. He went off to college on a basketball scholarship, leaving Karen behind to raise their son Lucas alone. When Dan's dream of a basketball career didn't work out, he returned to town with the wife he met in college and his new son, Nathan.

Now a wealthy businessman and one of the biggest fish in the small pond of Tree Hill, Dan lives his basketball dreams through Nathan. His actions have had a ripple effect on many people in the town. While Karen struggled to raise Lucas without a father, she remained friends with Dan's older brother Keith (Craig Sheffer, A River Runs Through It). Keith is Lucas' biological uncle and has served as his surrogate father over the years. His connection to Lucas is complicated by his attraction to Karen, and he is haunted by the possibility that he and Karen might have ended up together - and the hope that they still could. Karen's entire adult life has been focused on her son, but now that he's on this new road, she can no longer protect him.

Lucas and Nathan's rivalry on and off the court has even brought back old emotions for the grizzled basketball coach, Whitey Durham (Barry Corbin, Northern Exposure). Whitey coached Nathan's father, Dan, when he was the school's star player, and now he is coaching both of Dan's sons. He knows he is partly responsible for Dan's decision to not give up his scholarship when Karen became pregnant, and he has to juggle conflicting responsibilities and loyalties toward the two boys.

Years in the making, a deep and bitter conflict slowly unfolds as the two boys struggle to come to terms with who they really are and with a father who has chosen to live vicariously through one son while ignoring the existence of the other, and that conflict affects everyone in their tangled web.