A coming-of-age drama centered around two fourteen-year-old boys who encounter a mysterious fugitive hiding out on an island in the Mississippi. Intrigued by this man, they enter into a pact to help him evade capture and reconnect with the love of his life. Though it is hard for the boys to discern truth from fiction when it comes to Mud, it isn't long until their small Arkansas town is besieged by a beautiful girl with a line of hunters in tow.