Following genetic modification there are the two distinct classes that divide society, the cian and the pleb. Larkin was born a pleb, the lower side of society, each with their perfect cian match, forced to be a living incubator for organs that the cian will someday need due to the extensive cosmetic modifications that the wealthy enjoy. When the first accident in 100 years arrises resulting in the premature death of her cian Larkin is "asked" to fill in, forcing her to abandon her own society as they prepare for slaughter and enter into a seemingly perfect world with dangers she can't even begin to understand.