In this raucous romantic comedy, John (Owen Wilson) and his buddy Jeremy (Vince Vaughn) are emotional criminals who know how to use a woman's hopes and dreams for their own carnal gain. And their modus operandi? Crashing weddings. Normally, they meet guests who want to toast the romantic day with a random hook-up. But when John meets Claire (Rachel McAdams), he discovers what true love -- and heartache -- feels like.