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• A standalone novel
• Focuses on the Officio Assassinorum
• Published by Black Library in 2022
• A grimdark espionage thriller
• 359 pages

When a distant yet crucial world threatens to secede from the Imperium, the Officio Assassinorum dispatches a group of its finest agents to replace the planet’s monarch with someone more favourable. But when you’re working with trained killers, can you really trust anyone . . ?

What a book this is. As Black Library readers will be aware, there’s more to the grim, dark future than just endless battlefields. The various military factions may dominate the literature, but other groups find room to muscle in. The Inquisition is the most obvious of these, but now the Officio Assassinorum joins the fight. There have been a few bits and pieces here and there (Rath’s previous short stories, and the James Swallow Horus Heresy novel Nemesis among the more notable), but I believe this is the first current timeline novel centred around the Imperium’s assassins.

There are two elements of Kingmaker that really worked for me, and the first of these is how it functions as a love letter to spy thrillers as a genre. I’ve never been overly invested in that genre, but some of the tropes are familiar. Rath makes them all work, from the rivalry that borders on backstabbing, the change in priority as the mission inevitably goes sideways, and the uncertain allegiance of everyone involved. One early scene in which the our assassin protagonist emerges from the water clad only in his underwear is a clear nod to a rather famous James Bond scene. But this isn’t just a reassembly of espionage tropes and imagery. There’s a uniquely Warhammer 40,000 slant to the story. The undercover operative is a shapeshifter (Sycorax, whether playing herself or wearing another face, is the novel’s most interesting character), and the target’s indomitable bodyguard is a mech suit. As an aside, the subtlety of assassins and the bang-crash-wallop of armiger mechs goes together far better than anyone could have expected.

But what really sets this book apart is its use of found documents. It’s odd that found footage films tend to bore me, but give me a book that could exist within its own continuity, and I’m a very happy man. Kingmaker is full of interrogation transcripts, reports, and even the odd piece of poetry that all serve to make the world that little bit deeper. The transcripts in particular are an excellent innovation. Not just because they allow for quick deliver of dialogue, but because they remind the reader that the characters are constantly under surveillance. The reports go a step further, suggesting that there is an intended, in-universe reader for this text, and you can’t help but wonder who that might be. Rath also pulls off, very early in the novel, one of my favourite descriptions of a clandestine figure, noting simply that their appearance is too confidential to be set to paper. We may be able to enjoy this story, but we don’t have a high enough clearance level to fill in all the gaps. Because what kind of self-respecting secret organisation of assassins gives you all the answers?

Like a lot of spy films, Kingmaker does lose a touch of subtlety at the very end. But by this point the action-packed climax is deserved. And let’s be honest, when you go to the planet of big stompy robot suits, you want to see them hitting each other. That’s just human nature. And like all good spy films, there’s a stinger at the very end that hints at what a potential sequel might dive into. If Rath does return to the Officio Assassinorum, I’ll be first in line to pick up a copy.

Did you enjoy this book? If so, you might also like:
Agents of the Imperium (Audio Drama)
The Infinite and the Divine, by Robert Rath
Ironclads, by Adrian Tchaikovsky