Bilson and Carmack played Summer and Luke, respectively, on the FOX teen drama. The cast also included Peter Gallagher, Benjamin McKenzie, Adam Brody, Mischa Barton, and Kelly Rowan. FOX cancelled The O.C. in 2007 after four seasons.
Check out a photo of the two reuniting on set:
What do you think? Are you a fan of The O.C.? Do you watch Nashville?