Deep within the heart of the jungles of Far Payit is a city lost to time and the modern people of Maztica. Long ago abandoned by its people, it holds a deadly secret deep beneath its ruined surface, a secret held safe by a tribe of inhuman guardians. A secret that has remained inviolate until now. A cleric of the church of Helm has disappeared. A piece of a map to the lost city of Ixtzul has been found. Great armies of ants perform deadly assassinations. And in the jungle, a new leader has appeared, promising power to those who follow her into the forbidden vale. Now the heroes must follow as well, to uncloak the mystery and prevent the unleashing of a deadly force on the surface world of Maztica, a force that threatens both people of Payit and the newcomers' civilization in Helmsport. Should the heroes fail to defeat the endless armies of their foe, all in Maztica will perish!