In the middle of the twenty-second century, over three million people live in underground cities below the moon’s surface. One city-state, the Society of Cousins, is a matriarchy, where men are supported in any career choice, but no right to vote—and tensions are beginning to flare as outside political intrigues increase.

After participating in a rebellion that caused his mother’s death, Erno has been exiled from the Society of Cousins. Now, he is living in the Society’s rival colony, Persepolis, when he meets Amestris, the defiant daughter of the richest man on the moon.

Mira, a rebellious loner in the Society, creates graffiti videos that challenge the Society’s political domination. She is hopelessly in love with Carey, the exemplar of male privilege. An Olympic champion in low-gravity martial arts and known as the most popular bedmate in the Society, Carey’s more suited to being a boyfriend than a parent, even as he tries to gain custody of his teenage son.

When the Organization of Lunar States sends a team to investigate the condition of men in the Society, Erno sees an opportunity to get rich, Amestris senses an opportunity to escape from her family, Mira has a chance for social change, and Carey can finally become independent of the matriarchy that considers him a perpetual adolescent. But when Society secrets are revealed, the first moon war erupts, and everyone must decide what is truly worth fighting for.