Peter Gallagher Sandy Cohen Actor Ben McKenzie Ryan Atwood Actor Kelly Rowan Kirsten Cohen Actor Adam Brody Seth Cohen Actor Mischa Barton Actor Rachel Bilson Summer Roberts Actor Melinda Clarke Julie Cooper Actor Alan Dale Actor Olivia Wilde Guest Star Michael Cassidy Guest Star Shannon Lucio Guest Star Barry Newman Guest Star Kim Delaney Guest Star Christopher Lawford Guest Star Kathleen York Guest Star Danielle Bisutti Guest Star Deirdre M. Smith Guest Star Josh Schwartz Executive Producer Doug Liman Executive Producer McG Executive Producer David Bartis Executive Producer Robert DeLaurentiis Executive Producer