Disclaimer: I received an e-arc of this book by the publisher Tenebrous Press.

This book accompanied me on my trip to the ocean last week and I honestly can't imagine a better place to read this (except directly on a ship in the middle of the ocean maybe). The prose is lush and inviting, painting the ship in such vivid detail that I was often picturing myself in Isaiah's place (that I was actually able to smell salt water while reading probably helped make it even more immersive, but even if I hadn't been by the ocean, I think I would have been able to picture it clearly). And yet the prose never becomes over the top or takes away from the flow of the story, which I found really well done!
The story follows the crew of the Merciful after they find a living man in the belly of a whale and as if that wasn't unsettling enough soon things will take a turn for the worse. The horror of this book is incredible! It is so tense at times that I found myself nearly unable to put it down, reading nearly every free moment during my vacation until I had devoured it. It is also one of the few books where the horror I read actually turned my stomach (during one of the more... gross and horrifying scenes of the later third of the book I found myself so unable to put it down and so I read on while waiting for a plate of seafood I had ordered at a restaurant... I would not recommend recreating that experience unless you have a strong stomach! I am still glad I hadn't gotten anything with eels, but yikes that scene! Amazing and again, I loved it, but wowzers, was it gross!). I loved every second of this book, from the tense and claustrophobic scenes to the very gross ones and the tender ones as well.
It takes the best of ocean horror (the incomprehensible vastness, the isolation, the many, many scary things down there, the fact that you cannot leave) and combines it with a scathing critique of capitalism and its horrors (its incomprehensible vastness, the isolation of work, the many, many scary things in it, the fact that you cannot leave) as well as body horror (the isolation of being disfigured/disabled/a visible other, the many, many scary things that can be done to a human body, the fact that you cannot leave your body) into a masterful creation following one sailor as his ship turns into a haunted house filled to the brim with inevitable creeping dread and the knowledge that one way or another you are stuck and truly and utterly fucked. In the middle of it there are also some tender and lovely scenes, which enabled me to breathe deeply and hope, before I was tossed right back into the stormy waves of horror and I adored that as well.
So if you can I would advise you to take this book to the ocean with you this summer, sit in the sun and shiver from terror as you find out what exactly happens to the Merciful and its crew.