: Peyton is targeted by a "Psycho Derek" (Ian Banks), who impersonates her biological half-brother. She eventually meets her actual brother, a Marine also named Derek, who helps her confront her trauma.
: Brooke and Lucas officially break up after she realizes his growing feelings for Peyton. By the middle of the season, Lucas and Peyton finally begin a serious relationship. One Tree Hill - Season 4
Season 4 of One Tree Hill (2006–2007) is the final year of high school for the main characters, focusing on the closure of their adolescent lives and the resolution of the series' darkest mysteries. It was the first season to air on The CW network following the merger of The WB and UPN. : Peyton is targeted by a "Psycho Derek"
: Haley and Nathan navigate the challenges of being teen parents after discovering they are expecting a son. Nathan becomes entangled with a loan shark named Daunte, leading to a point-shaving scandal that threatens his basketball future at Duke. By the middle of the season, Lucas and
: The Ravens play for the State Championship; Peyton confesses her feelings to Lucas.