Twin brothers, Seth and Eli are Keylanders brought up within the privileged and protected Eastern Key. Keylanders, the boys are told, must keep within their walls to avoid the filth and disease spread by the Droughtlanders - those who struggle to survive on the parched land between the keys. A chain of terrible events begins to unravel the life they've all known and will pit brother against brother in a life-or-death struggle between two worlds.