When a virulent plague threatens to extinguish humanity across the galaxy, an investigator is dispatched to the isolated planet of Grass to uncover the secret behind its inexplicable immunity. Marjorie Westriding Yrarier must navigate the rigid, aristocratic social structures of the planet’s human colonists while contending with the mysterious, indigenous species that predates human arrival. As she peels back layers of local tradition and religious dogma, she faces opposition from powerful families who guard the planet's history with lethal intent. The narrative unfolds through a blend of political intrigue and anthropological discovery, revealing the physical and existential constraints of a world defined by its endless, alien flora.

This work is widely regarded as a significant contribution to ecological science fiction, noted for its intricate world-building and thematic depth. Readers often highlight the author's ability to weave complex social commentary into a compelling space opera framework. The narrative is frequently praised for its refusal to provide easy answers, instead challenging the audience to consider the long-term consequences of human colonization. The book remains a staple for those interested in the intersection of biology, sociology, and speculative fiction.