After a global disaster reduces Earth's human population to pre-industrial levels, survivors of western civilization divide into two groups: one recreates society following pre-disaster norms, while the other modifies human emotions to prevent a recurrence of the catastrophe. Those in favor of recreating society, referred to as the "Randoms, " migrate to Western Europe, while the proponents of a redesigned human existence, known as the "Modifieds, " settle in North America. Centuries after the division, two young women from the Modified faction are given the opportunity to visit the Random community. After their exploration, they each face a pivotal decision: whether to remain on Random or return to their homeland, Modified.