This book was such a good time. I don't read too many books that would classified as horror, and not much adult fantasy either, but this book was just about everything positive I had hoped it would be. It's violent and gruesome and cool and well written and full of interesting people who all have unique characters and motivations.

My only two negatives were both pretty small things. For one, the climax was a bit iffy for me. Like I know there has to be a big revelation at the end, but honestly, after all the murder and all the gore and all these characters we've grown to love have suffered so much, I didn't particularly care about the big moment at the end. It somehow seemed less than a lot of what had come before.

The other tiny issue was just the amount of science included. Sometimes I got a little lost in all the science talk. But also, the cast is literally just a bunch of scientists all crammed together on a boat doing research, so of course it's going to be science-y. It's hard to really blame it for that.

One thing I particularly enjoyed was the cast of characters. Every single one felt like a real person with a distinct personality. I so often expect horror characters to fall into tropes (which is really unfair and due to my lack of experience in the genre, I'm sure), but I really enjoyed them all here. There are a lot of moments in this book that are rather predictable and expected, just based on how the world works. If you decide to go swimming with killer mermaids, they will probably kill you. So as the reader, I wasn't always surprised. But despite this, all of the deaths mattered. They all meant something to me. I would so much rather predict what's going to happen and have it matter to me than be surprised at every turn and not care about the actual events.

I also just thought it was cool. Like the killer mermaids were cool. I liked how they were described and handled. I liked how the story unfolded. I liked that it wasn't afraid to kill people who mattered or end storylines just because the characters involved had perished. I really liked the writing style. This whole book kept me entranced the whole time. It wouldn't surprise me if this winds up as one of my favorites of the year. Everything about it was just so well done.

I'm obviously not super well read in the genre, but if it sounds interesting to you, I'd highly recommend picking this up. It was very well worth the time.