On a distant planet, in a land simply referred to as "The Beautiful Place," a civilization slowly evolves. A man by the name of 37, a celebrated hunter who spends his free time pondering the rational wonders of arithmetic, is tasked with protecting The Beautiful Place from invasion.

Meanwhile, another city-state, Newtown, is intent on destroying 37's beloved home. 37 defeats Newtown's army and comes away from his victory with an important and fascinating prisoner: Asha, the daughter of Newtown's leader.

Asha is an unpleasant captive who frequently tries to escape and has an annoying habit of challenging 37 at his own mathematical games. He's distracted from his growing interest in her, however, when invaders once again threaten The Beautiful Place. The mysterious, roving not-quite-people are bent on destroying Newtown, and The Beautiful Place is next.

The citizens of The Beautiful Place are shocked by the brutality of the not-quite-people, and 37 rallies an army, and, with the help of the fiery Asha, hatches a plan that harnesses the power of the great rivers themselves. If the waters can't save them, there will be no place left for 37 or any of his companions to call home.