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.
Brooke deals with the mounting financial problems at Clothes Over Bro's; Julian starts a new film project; Alex and Chase spend an afternoon together.
Nathan considers leaving the NBA; Victoria and Brooke try to handle the company's financial problems; Chase learns 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.
As the wedding approaches, Brooke tries to connect with Sylvia, while Julian looks for his best man at a guys' poker night. Meanwhile, Nathan struggles in his new job, while Haley's counseling abilities are challenged, and Skills returns to town with a new friend.
Nathan’s career as an agent takes a big step forward when he visits Atlanta, while Haley consoles Jamie regarding his new braces. The drama between Brooke and Sylvia finally comes to a head, and Chase makes a decision regarding Mia and Alex.
The gang gathers at Nathan and Haley’s to spend Thanksgiving with friends and family.
Brooke and Julian go skydiving, while Haley sets up a concert at Tric featuring Kid Cudi. Meanwhile, Quinn sneaks out of town to visit a familiar face.
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.
Brooke and Julian’s wedding day is finally here. Dreams become reality, secrets are revealed and wedding hookups are inevitable.
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.
Secrets, sex games and shoelaces are all involved 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.
As Brooke and Haley prepare to re-open Karen’s Café, Nathan and Clay hit the road looking for new prospective clients. Meanwhile, Chase leaves for the Air Force leaving behind a disappointed Alex and Chuck, and Mouth and Millicent begin their new morning show together.