Ancillary Justice is a science fiction novel written by Ann Leckie. It is set in a future where an artificial intelligence named Breq seeks revenge against the ruler of an interstellar empire. The book explores themes of identity, gender, and power dynamics. Ancillary Justice received critical acclaim for its unique narrative structure and thought-provoking exploration of social issues. It is a compelling read for fans of space exploration and thought-provoking science fiction.