Ancillary Justice is a science fiction novel written by Ann Leckie. It is set in a future where an empire known as the Radch controls numerous star systems. The story follows Breq, a former starship AI who now inhabits a single human body. Breq seeks revenge against the Radch for the destruction of her ship and crew. As Breq navigates the political intrigue and cultural complexities of the Radch empire, she grapples with questions of identity, free will, and the nature of power. Ancillary Justice won multiple awards, including the Hugo, Nebula, and Arthur C. Clarke Awards, and is known for its exploration of gender and colonialism.