The O.C. Star Mischa Barton Joins the Cast of The Hills Reboot

Mischa Barton is returning to the small screen — and making her reality TV debut.
A source confirms to PEOPLE that the actress has joined the cast of The Hills reboot.
Though she never appeared on the original series, which aired for six seasons from 2006-2010, Barton, 32, has a special connection to the MTV show. At 17, she was catapulted to fame for her starring role as Marissa Cooper on Fox’s The O.C., which premiered in 2003 and became a cult ph