The impending marriage between Caleb (Alan Dale) and Julie (Melinda Clarke) affects different people in different ways at the O.C. Having been asked to be maid of honor, Caleb's daughter Kirsten (Kelly Rowan) helps organize the wedding shower with Julie's daughter Marissa (Mischa Barton). Angered by recent events, Marissa schemes to spoil the wedding by inviting a most unwelcome guest. And Julie's ex-husband, Jimmy (Tate Donovan), ends up in a ticklish situation with Kirsten's wild sister, Hailey (Amanda Righetti). Elsewhere, Seth (Adam Brody) has an uncomfortable meeting with Summer's (Rachel Bilson) father, and Theresa (Navi Rawat) seems curiously anxious to avoid Ryan (Ben McKenzie).