We were created by the Bestower, and placed on the world to rid it of its native life, unpleasing to Him. He gave us the living Bestowed to sustain us and replace what was there before. Thus say the priests, but now that myth is questioned: Native life has evolved; why not ourselves and the Bestowed that came with us? Are not all native, and necessary for survival? The evidence is contentious: Exterminate, or conserve? There is increasing dissension and the threat of war.In this struggle, a policeman, a conservationist professor, a refugee, an archaeologist, an archpriest and many others play their parts. Amid the rising tension, a historian digs deep into the myth and its origins. It is, though, the development of her physicist husband's wild cosmological theories that add to the confusion; material can be made to vanish, but to where, and how? It is a masterful colleague who sees a practical use for the discovery, and by trial and error, the great Evaporator is developed in secret, its true purpose concealed. As rumours abound, both sides in the conflict seek to prevent its use. At the last moment, an attempt at sabotage has far-reaching consequences.