Owen Morello is a former alcoholic and drug addict who moved to Tree Hill and became a bartender at Tric. After meeting Brooke Davis they two shared flirtation until becoming a couple. However, after Brooke decided she wanted motherhood Owen got scared and fled the town. After uniting with Nathan who starteed playing Slamball he tried to apologise to Brooke who refused to take him back. He eventually left town after sleeping with Millicent and ruining his chances with Brooke.
Owen had a horrible childhood and got addicted to heroin early on, but Owen turned his life around and became sober for 8 years which Chase Adams helped him with. Owen and Chase had a close friendship and moved in together after high school.
Owen's first apperence in Tree Hill was at TRIC, the bar he managed. For a short time Owen rejected Brooke Davis' advances until he flew to New York with her in which they found Rachel Gatina who Owen knew from his junkie days, who had overdosed and they bring her back and try and help her stay sober but are unable. Owen and Brooke shared a short fling until Brooke said she wanted to adopt a child and Owen then ran away.
Owen was first seen on the team that Nathan Scott played for and helped him throughout his career in Slamball. Owen tried to get Brooke back, which later failed. But Sam, Brooke's foster daughter tried to help Owen and they bonded. And finally after trying endlessly to win Brooke back over, Owen turned back to alcohol, which resulted in him and Millicent Huxtable having a one night stand, taking her virginity. Owen Later left Tree Hill to recover from his relapse and leaves Chase in charge of the Bar.
While at AA meetings he once again meets Millie who too has become addicted to drugs and alcohol and they bond over their experiences and form a friendship, despite jealously from Millie's then ex-boyfriend Mouth.