Spensa has proved she is one of the best starfighters of the Defiant Defense Force, but she embarks on her most dangerous mission yet when the Superiority, the governing galactic alliance determined to dominate all human life, initiates a galaxy-wide war. To make matters worse, Spensa knows the weapons the Superiority plans to use: ancient, mysterious alien forces that can wipe out entire planetary systems in an instant called Delvers. Now, she must travel to the Nowhere and find a way to stop the Superiority once and for all.
