Moon has spent his life hiding what he is, a shape-shifter able to transform himself into a winged creature of flight. Just as Moon is once again discovered and cast out by his adopted tribe, he discovers a shape-shifter like himself, but the stranger doesn't tell him that his people face extinction at the hands of the dreaded Fell.

Martha Wells is the author of more than a dozen science fiction and fantasy novels, including the Ile-Rien series (The Death of the Necromancer), the Murderbot Diaries series (All Systems Red), and the Books of the Raksura (The Cloud Roads). Her work has won the Nebula, Hugo, and LocusAwards, been nominated for the Compton Crook award, and been published in eight languages. Wells lives in College Station, Texas.