Haley is surprised when her older sister Taylor comes to town, but not as shocked as Nathan, who recognizes Taylor from a past tryst. Brooke and Felix decide to become boyfriend and girlfriend. Jake makes a special visit to Peyton. Anna tells a secret to Lucas.

Nathan comes clean with Haley about his past relationship with Taylor, although Haley continues to email Chris without telling Nathan and Taylor finds out. Lucas and Karen remain at odds over his refusal to take the HCM test. Keith proposes to Jules. Meanwhile, Brooke fights for better working conditions at her new job. Lucas decides to take the HCM test.

When Michelle Branch & Jessica Harp from the band "The Wreckers" perform at TRIC, Haley realizes her passion is to pursue her music career. Meanwhile, Lucas decides to move in with Dan, straining his relationships with both Karen and Nathan. Brooke runs for student council president, but quickly realizes she is taking on more than she bargained for. Peyton and Jake's friendship grows stronger. Brooke finds out that Mouth broke her car window. Lucas gets his HCM results and aren't what they turn out to be.

On his way home from seeing Haley, Nathan stops to visit Taylor hoping for some fun and maybe more. Meanwhile, Anna gets a surprise visit from her ex-girlfriend and is inspired to tell her parents about her sexuality. Also, Lucas works with Andy to bring Dan down, Karen puts her foot down with Brooke. Peyton and Jake continue to hide baby Jenny from Nicki.

The Scott family joins Haley on the last leg of her tour, while Brook and Julian reconnect after their 6-week break. Clay and Quinn try to figure out how to move forward after his public declaration of love, and a post-rehab Alex tries to make amends with herself and the people she's let down.

Nathan tries to keep Haley calm after Taylor shows up at their house with Quinn’s ex-husband in tow. 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.

Brooke and Julian try to find a balance between their personal lives and work as the movie shoot begins. Nathan and Haley receive a surprise visit, and Clay supports Quinn as she faces some unexpected news., Alex sets her sights on Alexander, and Millicent finds herself struggling with temptation.

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