he third season of The O.C. commenced airing in the United States on September 8, 2005, concluded on May 18, 2006, and consisted of 25 episodes. The first ten episodes of season three aired Thursdays at 8:00 p.m. ET in the US on FOX, a terrestrial television network; however, from January 12, 2006 onwards, The O.C. was shifted to a later time of Thursdays at 9:00 p.m. ET.
Following on from season two, the series continues to follow the characters' lives in the wealthy community of Newport Beach, Orange County, California, with the main characters entering their final year of high school. Series creator Josh Schwartz said he wanted to explore the characters moving away as he "didn't want to be one of the shows that stayed in high school too long". He added that "graduating from high school is such a seminal moment for kids and parents. It's something we knew we wanted to mine and explore." The season revolves around Ryan Atwood's savior complex causing trouble, and Seth Cohen's lies posing problems in his relationship with Summer Roberts. Seth's mother Kirsten attends rehab in an attempt to put her life back together, while her husband Sandy assumes leadership of the Newport Group after Caleb Nichol's death and finds himself the heir-apparent to a legacy of scandal, and Marissa Cooper spirals out of control after her younger sister Kaitlin causes trouble on her return home from boarding school. The season was released on DVD as a seven disc boxed set under the title The O.C.: The Complete Third Season on October 24, 2006 by Warner Bros. Home Video.Overview from themoviedb.org