The O.C.: The Showdown

Zach and Seth face off for Summer's affections. Reed convinces Summer to sign on to the "Atomic County" launch party, but when she appears in costume, it sends the boys over the edge. Marissa has a hard time dealing with Ryan after what happened with his brother, Trey. Caleb issues divorce papers to Julie and lets her know he has incriminating information, including pictures. Kirsten continues to hit the bottle, but when she tries to return home to Sandy, she finds disaster on the road.