The World of fourteen year-old Tendeleo Bi is small, safe, stable: school, farm her father's church, the village of Gichichi. Then one night, the Chaga comes, and everything is different. Advancing across the plains of East Africa at ten metres every day, this alien infestation transforms terrestrial ife into something strange, perilous, wonderful, and nothing can stop it. Her village destroyed, Tendeleo becomes a refugee, with one need that drives her on: a place she can call home. Trapped between the relentless march of the Chaga, the UN and Nairobi Street gangs, her story moves across a southern hemesphere being terraformed into someone else's terra and byond: to a love that transcends continents, worlds, and a humanity on the edge of a staggering evolutionary leap, and that, like the Chaga, will transfirgure everything it touches.