First off, I'll freely admit that I picked this book up from my local library mostly based on the cover and blurb, knowing literally nothing about it prior to that. Which is fairly unusual, since I usually know at least something about the majority of new SFF being published or at least its author... instead, The Interminables apparently passed me by completely when it was published in 2016.
The basic premise of the book is that back in 2010, an age-old magical deity arose once more and attempted to destroy the planet, only to be pushed back and eventually defeated by a mysterious cabal of wizards known as the Twelfth Hour. Understandably, this left massive amounts of damage behind and the Twelfth Hour still exists to try and keep order in what's left and also deal with any new dangers that might arise, as well as the things left behind by the events of 2010. There is, of course, something nasty left behind that still needs to be dealt with for everyone to survive...
Our protagonists are a member of this cabal who has discovered a way to become immortal by taking tiny fragments of time from everyone he meets and the literal concept of War, in what starts out as pretty much a sausagefest. While it's eventually revealed that their boss is a woman, there seems to be much made of how unfeminine she is and the other main female character's role is apparently to motivate one of the main characters through having died, until (of course) it's revealed that she didn't die after all. There's also a slightly clumsily not-dealt-with sub-plot where one (male) character is in love with the other who thinks he's straight because he was married back when he was alive.
All in all, it's not the worst thing I've ever read and it kept me turning the pages to the end, but it could have been so much better. I got a bit annoyed with the fact that not much really gets resolved in terms of the relationships between the characters and it's clearly left as a set-up for one or more books to follow (the first of which, Immortal Architects, my library also has a copy of somewhere so I'll probably get to read it at some point).