If you're a Black Templars fan this is a 4 star. If you just like 40k then this is a 3 star read. Based on my rating, I am a BT fan and sought out this book specifically because it was about the Black Templars.
Read physical copy.
Mild spoilers:
This is definitely a tier above "bolter porn" but still falls into the repetitive BT trope of "I will die on this world" pioneered by Helsreach. With that being said, the plot is quite lively and moves fast. I kept thinking to myself that this book could be made into a movie as the plot is quite cinematic.
The main protagonist is layered and even the "hardcore Black Templar" character you always get in BT fiction has a great arc. The main baddie is layered in a way that I found unique and interesting, however I found that the baddie was almost too layered, trying to make the reader emphasize too much with him, to the point that there is an even bigger baddie thrown in in the third act. I didn't love the baddie's arc, but I did find it an interesting an unique take. The climax was well done for everyone including our protagonist, no deus ex machina thankfully, but I felt like the climax was not well done for the baddie. The baddie's arc was built up only to under-deliver in my opinion. I like my 40k fiction written in two ways, either the clear good guys and bad guys, or everyone is a shade of grey. Yes, I know there are no good guys in 40k, part of the reason I like this universe, but if a story presents our protagonist and his faction as the clear good guys, I don't want the bad guys to have shades of grey. I felt the lowpoint of the book came when our baddie was rooting for our good guys - the book kind of jumped the shark here, "And yet, as he watches the dark forms of the Black Templars race across the [redacted: spoilers], he finds himself hoping" (pg. 238). Fortunately, the book gets back on track, but with this, it opens up a tall order to fulfill in our baddie's arc that the book can't quite deliver on.
One of the things I liked most about this book was the unique take on the ship, the Dauntless Honour and how the "computers" or void looms/machine spirits as they call them work with the various sensors. This was really interesting since in the 40k universe they don't use AI (called Abominable Intelligence after their lifted-straight-from-Dune version of the Butlerian Jihad, the War with the Men of Iron). There are a few sequences in this book regarding the ship collecting and processing data - which as I type now sounds super boring haha - but I actually found fascinating.
I felt like our apprentice surgeon character was interesting, especially her interaction with her father and with the space marines, but there was not enough regarding her. Like her own arc is happening then she just disappears for what seems like 100 pages, to the point where I started wondering what happened. Then when we get back into her perspective, we've kinda lost interest and forget what's going on with her. It almost feels like 10 pages or so with her were cut to keep this book under 300 pages?
The perspectives from the baddie were a cool concept that I liked. I just think the author tried to make the baddie too much of an empathetic character. I especially liked the perspective swapping during the climax, cool concept that delivered the action and not a concept that I can remember seeing done before so props to the author for that.
Overall, if you like 40k and Black Templars, you'll like this book. If you just like 40k you likely enjoy this book as well. A worthy addition to the Black Templar lore!
Happy reading!