A turn-based tactical Western RPG in which the Chosen One is tasked with exploring post-nuclear California to locate and retrieve the fabled Garden of Eden Creation Kit for their famine-stricken tribe, while coming into contact through branching dialogue trees with numerous tribes, factions and micro-civilizations, each with their own virtues, vices, socioeconomic situations and political agendas.

In 2241, the primitive Arroyo suffers the worst drought on record. Faced with the calamity, the village elder asks the direct descendant of the Vault Dweller, referred to as the Chosen One, to perform the quest of retrieving a Garden of Eden Creation Kit (GECK) for Arroyo. The GECK is a device that can create thriving communities out of the post-apocalyptic wasteland. [3] The player, assuming the role of the Chosen One, is given nothing more than the Vault Dweller's jumpsuit, a RobCo PIPBoy 2000 handheld device, a Vault 13 water flask, a spear and some cash to start on his mission.