For seventeen years the division of the sexes has kept the post-nuclear world peaceful. Glori Rhodes is like most other fees her age: she can bench her body weight, and knew beast counter-attack moves by the time she was seven. When her mother gives birth to a baby beast, Glori can't help wondering: What really is the difference between us and them? At five years of age her brother is snatched in a raid. Glori and her friend, Su, infiltrate the City of Beasts to get him back. Glori, Sway, and a motley cohort of friends will go to the ends of the earth to find her little brother... and maybe save their divided world while they're at it.