A riddle rarely makes sense the first time you hear it. The connection between Dane, a bully, and Billy D, a guy with Down Syndrome, doesn't even make sense the second time you hear it. But it's a collection of riddles that solidify their unlikely friendship. Dane doesn't know who his dad is. Billy doesn't know where his dad is. So when Billy asks for Dane's help solving the riddles his dad left in an atlas, Dane can't help but agree. The unmarked towns lead them closer to secrets of the past.