Deb's cool younger brother, race pilot Cooper 'Coop' Lee, visits his favorite nephew Nathan and invites him and Lucas to Lowe's Motor Speedway (now Charlotte Motor Speedway), where the boys and his kid brother Jarret get a crash course from competitor Ray Green's daughter Daytona 'Toni' in not crashing for a taste of the race. Dan informs college about Andy's improper relationship with Karen- he must choose and gives his notice. Mouth fakes being drunk so Brooke can 'drive him home'; Erica is a real client, and hits on with him, kissing. Dan finds Deb wasted in the garden. At the day of the (private) race, competitive athlete Nathan's pride is hurt, so he tries to break the track speed record but crashes with bad long injury; the doctors tell Deb her blood is too 'rich' in pills to donate; Toni thinks Nathan was suicidal. Coach tells Peyton Jenny is safe in a small Florida town.

Lucas struggles with the decision of whether he should play basketball in the wake of Keith's death while Brooke forces Rachel to deal with a dark secret. Nathan and Haley's wedding reprise is put to the test and Peyton decides to visit Pete in Chicago.

It's the weekend of the Coastal Classic, and with Lucas sidelined, Nathan has to step up on the court against an old rival who shows an interest in Haley. Brooke and Mouth plot revenge against Rachel while Dan goes head to head with Nathan's Uncle Cooper. Also, Peyton makes a life-altering decision.

Nathan and Haley's wedding is a time of great joy. And great sadness. Peyton and Brooke fall out, Dan learns the truth about the fire, and Rachel gets publicly drunk....and publicly bitter.

The aftermath of the post-wedding car accident unfolds. Haley is deeply affected by Nathan's attempt to rescue Cooper and Rachel, Brooke confronts Lucas with her true feelings and Peyton makes a startling discovery. Pressured by the fact that someone might know he killed his brother, Dan assaults Deb.

As Nathan, Rachel and Cooper's lives remain precarious following the car accident, Brooke celebrates her 18th birthday but finds it diminished by her struggles with Peyton. Lucas and Karen come to terms with her pregnancy and with the pregnancy of someone close to Lucas, while Deb's past addictions intersect with Haley in an explosive manner.