Breq used to be a spaceship, or at least a fragment of the spaceship known as Justice of Toren. The ship controlled innumerable human bodies, known variously as “ancillaries” to the people of the interstellar Radchaai Empire and as “corpse soldiers” to the cultures and planets the Empire has conquered. Those soldiers used to be regular, innocent human beings who, if sufficiently healthy, were slaved to one of the Radchaai ships, their personalities more or less overwritten to become part of one of the Empire’s many-bodied artificial intelligences.

But note: Breq “used” to be a spaceship. Now, she is just Breq, a single person with one body, but with memories of being both an immensely powerful artificial intelligence and its army of soldiers. When we meet Breq, at the start of Ancillary Justice, the spectacular debut novel by Ann Leckie, she is hunting for a gun—a gun that may be able to kill Anaander Mianaai, the immortal and multi-bodied Lord of the Radch.

Ancillary Justice starts off alternating between two perspectives, who happen to be the same person. Sort of, at least. One set of chapters focus on Breq’s present, her search for the semi-mythical gun that may be able to kill the leader of the Empire she used to serve, and her encounter with a drug-addicted former officer of that Empire. The second set of chapters consists of flashbacks to Breq’s past, except she wasn’t Breq then— she was One Esk, a squad of twenty corpse soldiers serving on Justice of Toren, and at the same time she was Justice of Toren itself, serving during one of the Radchaai’s “annexations” (read: brutal subjugation of an entire planet’s population).

Ancillary Justice may quite possibly be the most unique and refreshing take on space opera I’ve encountered since I discovered the works of Iain M. Banks, years ago. It could also, in some ways, be read as a comment on some of that author’s works in specific and on the space opera genre in general— but more about that later.

This is a deceptive novel, one that will challenge many of the expectations you may have about SF as it eases you into its story. One of those expectations is the gender of its protagonist and side characters. Tell me you weren’t surprised when, in the second paragraph of this review, Breq turned out to be a she. Now multiply that surprise a hundredfold, and you will have an idea of what this novel does so successfully.

The language of the Radchaai Empire does not differentiate between gender. Breq uses “she” and “her” throughout the story to refer to other characters. Occasionally you only find out a few chapters later that one of those characters is actually male. Sometimes, Breq must force herself to pay attention because she realizes that people from other cultures may take offense to being called the wrong gender.

In this context, when someone refers sneeringly to Breq as a “tough little girl” in the very first chapter of the novel, it’s hard not to take it as a comment on the casual sexism so often displayed in SF—partly because of what Breq used to be, and partly because of the culture she belonged to.

The blindness to gender also has a much more bitter connotation, given the way the Radchaai deal with conquered empires, treating prisoners as bodies to be enslaved, whether they’re male or female. Depersonalization is a big theme of this novel: people are re-educated (read: brainwashed) or turned into ancillaries as a matter of course. It becomes clear fairly quickly that the Radchaai Empire almost makes Nazi Germany look like nice folks. Concentration camp guards probably didn’t really care about the gender of the people filing into the gas chambers either.

In that sense, the dispassionate tone of the chapters told from One Esk’s perspective is utterly chilling. The fact that she occasionally narrates from various viewpoints (the twenty bodies she controls) is only a small part of that. It’s really the sense that she’s part of a vast, horrible, and incredibly successful war machine—and the sense that most people inside that war machine believe they’re doing the right thing, spreading the equivalent of the Pax Romana across the universe. One Esk collects songs from the cultures the Radchaai have assimilated, then sings them, in harmony with the other bodies she controls. It’s one of the most chilling images I’ve ever encountered in a science fiction novel.

But then there’s that second plot, where Breq—again, one of Justice of Toren’s former components—is trying to bring change to the system. Every other chapter essentially shows Breq as a one woman revolutionary army. Ancillary Justice is the story of how she got from here to there, and while that story develops it also introduces the book’s spectacularly innovative and fascinating space opera universe. It’s almost impossible to believe that this novel accomplishes so much in under 400 pages.

So, about that Iain M. Banks comparison earlier. I should probably first explain that I tend to compare every space opera I read to his Culture novels, because in my opinion they’re the gold standard for the genre in almost every way. However, in this case, there were a few items that really struck my attention. Names like Seivarden Vendaai, for one, wouldn’t look out of place in a Culture novel. More importantly, the classification of ships (Mercy, Sword, Justice being different categories) reminded me of things like the ROU’s and GOU’s.

Those are all details, however, and probably could be traced back to other series too. Much more significant is the seemingly diametrical contrast between the two societies: the semi-anarchist, post-scarcity, almost Utopian Culture, and the fascist, dystopian Radchaai which goes as far as treating prisoners as a commodity, stockpiling bodies by the millions for possible future use. Both societies are highly reliant, if not governed by, impossibly powerful artificial intelligences, but whereas the Culture lets its human run free and wild, the Radchaai exercises the ultimate form of control.

And yet, both are, well, empires, right? One of the main ongoing plot threads in the Culture series is the way it interacts with other civilizations. Departments like “Contact” and “Special Circumstances” have subtle names—but you could have a long discussion about the ethical underpinnings of their philosophy as much as the Radchaai’s. Ancillary Justice makes the reader question the many forms of imperialism and colonialism as much as the perception of gender.

So, please forgive me for that long sidebar about an entirely unrelated series. I truly found it hard not look at this stunning debut novel as a deeply complex challenge to some long time SF tropes.

There’s a lot more to Ancillary Justice than what I’ve touched on here. Several SF planets and individual cultures. A set of incredibly subtle relationships and personal histories. A narrative tone that’s somehow at once dispassionate (which makes sense, given who’s narrating) and richly textured. On the negative side, I felt that the story did lose some tension towards the end, when the two threads merge. And, it’s the start of a series, which I wasn’t aware of when I started reading. Because of this, the ending felt like a bit of a letdown. I was ready to give this novel five stars on GoodReads, something I very rarely do, but I ended up settling for 4.5 because of those minor quibbles.

And yet. Ancillary Justice by Ann Leckie is, so far at least, the SF debut of the year. It’s a book that will have you reconsidering its many implications for a long time after you turn the final page. I can’t recommend it highly enough.