Kirit is a talented flier taking her flying test soon with a trading career already planned out. She thinks of everything in terms of trade and negotiation and is motivated to protect her friends, family, and community by succeeding. An encounter with a skymouth (feared monstrous flying creatures) brings her to the attention of the society’s guardians, the Singers. She reveals an ability that the Singers want to recruit her for, so they meddle with her test results and then blackmail her. She is fast-tracked through Singer training and learns there is more to the Singers, including a past that involve her family and that of her friend, Nat.
Wilde gives readers an imaginative world where humans can fly. It is fascinating how she gets into the details and mechanics of flying and how it works as society's main mode of transportation and connection to other communities. There are hints of some tragic past that has led the people to live in the sky. There are rigid laws that the people live by with precise procedures, rituals, and songs that govern every aspect of their lives. They add to the world-building by giving structure to the kind of world the characters live in and how it influences how they think and act.
The Singers enforce the laws and protect people from the skymouths. The Singers are also guardians of knowledge and history that is not generally known, so the people live in ignorance and blind acceptance. Their justice system for grievances and challenges to the system is determined through ritualized trial by combat. It sets up for a dystopia to be overthrown, yet it is not quite a dystopia because the people believe in the rightness of their laws and trust in the Singers to lead them and do the right thing. There are cracks in the system, where the laws or people enforcing them can be manipulated, and there is dissension among the general people and even the Singers, so it gets a little more complex than a battle of good versus evil.