On a mysterious green planet regenerated by fire, vibrant communities live in harmony with both its strange ecosystem and each other--until the day imperialist forces arrive. Char and her family are among the nomadic Summer people of Germinal who tend to the rich biodiversity of their world through reciprocity and ritual. They must forever travel to stay ahead of the walls of fire that approach like clockwork, bringing with them both loss and renewal. The flamewalls divide their world into threes: three seasons and three ways of life, keeping them from the Spring and Winter people, about whom they must never ask.  Char is the first to spot the off-world landing vessels bearing the militaristic invaders whose intentions are far beyond her worldview.  Graft is a captive servitor and personal attendant to the Conquis, leader of the vanguard forces. The last survivor of a culture annihilated by conquest, Graft is tortured by grief and determined to avoid notice, but he soon recognizes how unprepared Char and her people are to deal with the invasion.  After one unsettling discovery leads to another, the newcomers find the nature of this land troubling and its denizens odd--perhaps nonhuman. When the mission turns darker, the inhabitants of the violated utopia must learn how to defend themselves or lose everything.  Inversion stages an experiment in new possibilities of living, a tale of social struggle set in a wildly unique universe animated by questions of climate collapse and collective action. Aric McBay weaves a tale in the visionary spirit of Ursula Le Guin's The Dispossessed and Kim Stanley Robinson's Mars trilogy.