This another wonderful entry into the Sorn Soldier series. Each book is great, and slightly different from the others - I honestly don't know how the author comes up with these incredible ideas. I love the spooky tinge without it falling all the way into true horror.

I think the beginning of this book scared me more than any T. Kingfisher book before it. Alex is afraid of monsters in the abandoned coal mine and so am I. This is the third book in the Sworn Soldiers series and my second favorite. What Moves the Dead will probably always be my favorite but What Stalks the Deep was extremely enjoyable and I think the mystery felt more solid than it did in book two. I always end up feeling bad for T. Kingfisher monsters and this one is no exception. The reader knows our heroes are going to win because that’s how her books work but despite the terrible things her monsters do they are always complex in a way that makes my heart go out to them. I also love love love the weird biology that gets explored in this series. They feel very anchored in this world because of it even though I am very glad they are fiction. My only complaint is the length, I do love novellas but I wanted a bit more of the monster attacks before the end. Four and a half rounded up to five stars.

What Stalks the Deep by T. Kingfisher, another great book by Kingfisher that borders the line of horror and fantasy. I am always on the lookout for new books by this author.

I can never say good enough things about T. Kingfisher. She never fails to spark my imagination, make me laugh with clever witticisms, or terrify me with haunting creatures.

This is the third installment of the Sworn Soldier series and I don't think I'll ever get enough. This time, our main character Alex (whom I adore) is headed for West Virginia. I'm from the South and might be partial, but the setting was so captivating and horrifyingly familiar. There's nothing scarier to me than going underground, so all the scenes in the coal mine had me nervous with anticipation.

I devoured this in one sitting and as always, would have happily read 300 more pages. Out September 30th - you won't want to miss this!

Thank you to NetGalley and Tor for the ARC in exchange for an honest review!

4.5 out of 5 stars or 9 out of 10

3.5 stars

Kingfisher always comes through. And I love me some Alex Easton! This one did not feel quite as much on the horror side as previous books, but it still had those elements while more subtle.
Either way it was another banger for Kingfisher!

Another winner for T. Kingfisher. What I love about Kingfishers' books is that each one is uniquely dark but enjoyable to read. Highly recommend!

Alex Easton is back, and this time creepy things are going down in a coal mine in West Virginia. I am obsessed with both books set in Appalachia and this series, so getting my hands on a new Sworn Soldier novella that takes place in my second favorite literary setting (derelict English manor houses > Appalachia) was basically a mini Christmas in July.

Like the previous novellas in this series, What Stalks the Deep is creepy and humorous and suspenseful and and full of talk about pronouns. Easton is as amusing and witty as ever (and is absolutely, positively not claustrophobic). There's a missing person and a murder and some odd-looking creature roaming about the mine, and it's all quite entertaining and fun. And, as an added bonus, I've learned that I never ever want to explore an abandoned coal mine because they're scary and have tight spaces and can potentially blow up and/or suffocate you. Uh, no thanks.

II did find this one to be somewhat less horror-y than the previous installments. There are some ever-so-slightly scary bits, but nothing nearly as terrifying as the events of What Moves the Dead. In fact, the main creature in this one is kind of … cute? Well, okay, maybe not exactly cute, but I kept imagining it as sort of a mini Stay-Puft Marshmallow Man even though I'm sure that's not at all what Kingfisher had in mind. Also, the plot isn't particularly deep, but it's a sub-200 page novella so I'll give it a pass there.

Anyway, if you've enjoyed the previous two Sworn Soldier novellas, there's a pretty good chance you'll enjoy this one too. And great news — the ending of this book very strongly hints that it won't be the last in the series. Yay!

3.95 stars, rounded up.

Many thanks to NetGalley and Tor Nightfire for providing me with an advance copy of this book to review. Its expected publication date is September 30, 2025.

T. Kingfisher does it again. Devouring these books in a day because it's impossible to put down. The amount of originality and humor in a deeply suspenseful and scary story is immeasurable. This story brings back characters from "What Moves the Dead" with a parallel but completely original storyline. Requested to help in America, Easton gets a taste of the USA and the loudness and handshaking-ness of it all while exploring the terrifyingly dark and twisty coal mines of West Virginia. As if coal mines aren't claustrophobically scary on their own, Easton and Angus explore the mines searching for an unknown source of red light as it moves in the dark while searching for a lost soul. All the while, an alleged rabid bear lurks in the town, killing and harming residents. There is no rest for poor Easton, but many exciting thrills.

I'm always going to jump on the chance to get an ARC of a new Alex Easton book. They're just such a great character and one of my favorite things that Kingfisher does. This was another fun one! I think my high point is still book 2, but this was still super enjoyable. For this adventure, Easton goes to America to investigate someone who went missing in a mine, only to find spooky stuff within. It's a bit gory, but it still felt a lot more lighthearted than the last two books to me. Borderline cozy, to be honest. There's still a monster and a mystery, but it's not particularly tense. It's not necessarily a bad thing and is still a solid story, but I would kind of go in knowing that. It's funny, fast and even though it isn't particularly scary or anything, the monster is still pretty neat. Looking forward to the next one!

What Stalks the Deep is a follow up to What Moves the Dead, which I wholeheartedly enjoyed. WSTD has an intriguing plot that made me want to dive in immediately, which I did. I love reading novels set in beautiful, wild, mysterious Appalachia. There’s a mind bending and captivating story here, but I found the narrator’s voice to be too sentimental - sentimentality and a tendency to ramblingly reminisce are personality hallmarks of Alex Easton, but in this particular title I found that Alex Easton’s ambling thoughts overpowered a really cool plot.

T. Kingfisher is back at it again! The third installment in the Sworn Soldier series lives up to the hype, and Alex Easton is the begrudging chivalrous hero the world needs. Monsters aren't black and white, and T. Kingfisher does a phenomenal job of exploring that.

This was easily my favorite in the series. The pacing, the characters and the setting were all 10/10 and the creature...love it. Would absolutely read a full length book about them.

I love the Sworn Soldier series and Appalachian folklore/horror, and WHAT STALKS THE DEEP is an incredible combination of both! The pacing was perfect for a novella, and there was just enough horror to keep me cringing on the edge of my seat in the best way. I adore Alex Easton's narrative voice, and the coal mine was such an incredible setting. Another win from T Kingfisher for sure.

T. Kingfisher’s What Stalks the Deep is another absolute triumph in the Sworn Soldier series, spine-chilling, clever, and wildly imaginative. This time, Alex Easton finds themself far from the familiar landscapes of Europe and deep in the eerie shadows of a haunted coal mine in West Virginia. The shift to a U.S. setting breathes fresh life into the series, opening a door to an entirely new world of folklore, supernatural tension, and distinctly American horror.

The setting is pitch-perfect, claustrophobic, atmospheric, and unsettling in all the right ways. Kingfisher transforms the abandoned mine into a character of its own, full of secrets and dread. The creatures introduced here are delightfully original (and terrifying), reminding me once again why I would gladly read 87 more Alex Easton books if she would only write them.

As always, Kingfisher’s representation is thoughtful and welcome, and her voice remains one of the most unique and compelling in speculative fiction. Alex’s dry wit, courage, and reluctant sense of duty make them such a memorable narrator—and their dynamic with returning and new characters alike keeps the emotional core of the story grounded and sincere.

If you haven’t read the Sworn Soldier series yet, you’re missing out on something truly special. Mark your calendars, What Stalks the Deep releases September 30, and it’s not to be missed.

Special thanks to Netgalley and Tor Nightfire for the Advanced Reader’s Copy in exchange for an honest review!

I want to preface this with the following: I'll read anything T. Kingfisher decides to put in front of the world’s eyeballs and that goes double for the sworn soldier books.

This book, like the previous two books in the series, is a fun, eerie journey into someplace that is Not Right (a West Virginia coal mine) that contains something just beyond the edge of perception.

However, unlike the fungus in the first book and the maybe-ghost in the second, the titular thing that stalks the deep doesn't hit as hard as its predecessors. There's a bit of a bait-and-switch, which is great, but it makes the eventual climax-conclusion feel a bit more "wait, that's it?" than is effective. Overall, it reads more like a solid campfire tale than a capital A Adventure.

Last thought: needs more Angus.

This book is for fans of the first two installments who wanted the monster to be a little cuddlier.

Thank you to NetGalley for the opportunity to read an advanced copy!

"What Stalks the Deep" is another horror novella by T. Kingfisher in her "Sworn Soldier" series. It is highly recommended to read the other books before reading this one, though it could be read solo. Alex Easton, our soldier, comes to the aid of another friend to find his missing cousin, this time travelling to America to a West Virginia abandoned coal mine. Love Easton's sense of humor when faced with eldritch horrors and Kingfisher's worldbuilding. This is a strong entry into the series and a recommended purchase for fiction collections, especially those that have the other "Sworn Soldier" novels.

probably my favorite in the series so far. creepy, unsettling, but gay! a banger. can't wait to read the rest

Your favorite Sworn Soldier, Alex Easton, is back at it--steadfastly facing down eldritch horrors. Internally, sure...they're horrified and reluctant, but their courage and commitment to aiding friends inevitably wins out. This novella set in an a coal mine in West Virginia that's been abandoned each time someone new tried to make use of it. Denton must go in search of his cousin who went missing after exploring that abandoned mine, and knows that Easton is the only person who won't balk at the level of incomprehensibility they're sure to face. It's claustrophobic, it's heart-warming, it's tense, and it's another thoroughly enjoyable tale.

The charm of T. Kingfisher's Sworn Solder remains untarnished--may it never wear off.

Alex Easton is back—reluctantly, grimly, and somehow hilariously—as they’re pulled into yet another creepy mystery, this time in the dark guts of a supposedly haunted coal mine in West Virginia. They didn’t want to come to America. They definitely didn’t want to go spelunking into a horror story. But when an old friend asks for help? Off they go into the dark. Again.
I love these books. Every character feels like they’ve lived a whole weird life before they showed up on the page. The monsters? Top-tier nightmare fuel. Kingfisher is clearly embracing her inner Lovecraft—but with a beating heart and a sense of humor that old H.P. would’ve been too uptight to attempt.
This one’s moody, atmospheric, and quick—maybe too quick. I just wish these novellas came out a little faster or ran a bit longer so I could spend more time in this strange, unsettling world. Still, no question: five stars. I’ll keep showing up, flashlight in hand, for whatever’s stalking next.