Mysterious Fathoms Below

Vows of Vengeance #1

by J.A. Good

Every civilization, every culture has a story about the creature that lives in the sea, but what if they were all real?


Rosamund Bailey used to be in love, but as always happens, her heart ended in pieces. For the last year, she has tried to carve out a new life in London Society, but when her former fiancé’ returns with an ultimatum, Rose has to choose between herself and the family she loves.

Impulsive and reckless, Rose concocts a plan that may lead to riches, but is just as likely to end in a violent and ghastly death. Only one notorious Pirate Captain, a sea full of monsters, and a shared past stand in the way of her goals.After all, sunken treasure guarded by water wraiths and an ancient sea dragon are only minor inconveniences, right?

Genres: Fantasy, Romantasy, Pirates, Romance, Fantasy Romance, Slow Burn, Enemies To Lovers

410 pages, Kindle Edition

Published May 5, 2025

About the author

J.A. Good is the author of the adult fantasy romance Forged in Fire Series. She is a northerner living in Florida who’s love of books and new worlds inspired her to create her own. She is a pediatric intensive care nurse at night and a writer, mom, wife, and cat enthusiast during the day. When she isn’t naming all the dinosaurs with her toddlers you can find her staring at her book collection with her cats lamenting her lack of castles and magic.

Reviews

[Books_and_Crafts · Rating 5 out of 5]

Listen… *ah hem*

PIRATES OF THE CARIBBEAN MEETS BRIDGERTON!!!!!

This book was like a freaking movie playing in my head. The banter? Hilarious. The tension? Perfection. The pirates? Swoon worthy.

This is Pirate summer on the high-seas girlies. We’re battling sea monsters and falling for rogues. Don’t let this one sail away!

[Andrea · Rating 5 out of 5]

Let me start off by saying that this was a breath of fresh air. I am absolutely in love with this book. I couldn’t put it down. Bridgerton meets Pirates?! I mean, it’s literally the perfect combo. The female main character was amazing. All of the characters you meet in the book are so amazing you absolutely fall in love with everyone the story and the sea creatures Are so addicting. There was definitely great tension and yearning, which I absolutely need and adore in a book. I can’t say enough about this book if you love romantic if you love adventure if you love sexy pirates, you absolutely have to read this book.

[Emily Martin Julien · Rating 1 out of 5]

I am absolutely shocked by all the positive reviews on this book. By all metrics, I should have loved it. Pirates? Romance? Fantasy? A sassy heroine who, for once, isn’t a teenage chosen one or the tiniest daintiest woman to ever live? What could possibly be better?
Unfortunately, I have never been so beaten over the head with grammatical errors in my life (and this includes the summer I spent tutoring 8 year olds with remedial English needs). Did this book even have an editor? How did the author AND the editor reach adulthood without knowing the difference between when an apostrophe is needed to indicate possession vs a plural “s”? About halfway through the “book”, I started annotating (something I’ve never done in my life) and found blatant errors every few pages. The names of the sea monsters are spelled and capitalized differently just a few pages apart. Is it Corpse Cove or Pirate’s Cove? At one point they mention that it’s summer in The Drake Passage and back in London. This isn’t possible, due to the nature of our Earth and its separate hemispheres. @Editor and publishing house, if you are reading this please contact me as I have serious concerns about your weak grasp on the English language and detrimental contributions to the greater canon of western literature. I’m now interested in writing and publishing my own book, since apparently we’re letting anyone do this now.
Lack of editing aside, what is this plot? The FMC is so immature and says things so definitively at the end of every chapter, as if she’s Tumblr come to life. The plot is confusing and oddly paced, which could be forgiven as the first book in a series, but it was so difficult to get through that I am personally happy to leave Flynn Ryder I mean “Bash” in the hands of the randomly-appearing Royal Navy forever.

[Nezha · Rating 5 out of 5]

I LOVED THIS BOOK!
If this isn't on your summer tbr, what are you even doing??

This book was so well written, the snippets about The Mysterious Deep at the beginning of each chapter just pull you right in - I loved the sea monster lore. But what really makes this book are the characters, the pirates - I hope we get more about each of them and their backstories in the next book. Found family will always be one of my favourite tropes 🤌🏻

I can't wait to see the hell that Rose, Inu, Val and Dilly raise in book 2, I just know it'll be immaculate 🤭

[Krista · Rating 4 out of 5]

We get a unique storyline here. Interesting cast of characters. FMC got on my nerves sometimes with her judgmental views without knowing the whole story but she does appear to grow. It did stall in parts. REALLY wish I’d known beforehand that this was book 1 and not a standalone. I don’t know how I missed that. 😂 Not prepared for such an abrupt ending with so much hanging in the balance. And the wait begins……

[Christine Baker Nguyen · Rating 4 out of 5]

4-4.5! My first pirate themed romanasty and I’m very happy with it lol I love the writing style and and humor - scratched an itch in my brain and already got the second one! No crazy world building here- described as bridgerton meets pirates and I’d say that’s spot on

[Hannah Britton · Rating 5 out of 5]

I loved everything about this. Sea monsters, Sexy pirate captain, high society drama, and gross ex's. This was such a fun read, and I knew from the first few chapters that I was going to love this. I appreciated that there were tough conversations in this, that past trauma was a persistent theme, and not just introduced in the beginning and then forgotten about because our main characters are supposed to be amazing at everything. Rose is a spoiled brat, and gets a lot of wake up calls that are brutal and unrelenting, and from the mouths of the people she cares about most, and that was really refreshing. I am usually annoyed at naive and spoiled FMC's but this was well done, and you got to see a lot of her growth, and understanding of the real world outside of balls and pretty dresses of London socialites. Definitely Bridgerton crossed with Pirates of the Caribbean. I am sooooo excited for book two, and really glad I read this when I did so that I don't have to wait so long for book two. Give me villain eras and more sea monsters, I am ready.

[kelsie. · Rating 4 out of 5]

Who knew I had a pirate captain fantasy waiting to be unlocked? J.A. Good apparently. Mysterious Fathoms Below was really a lot of fun.
Rose was indeed a privileged brat for a vast majority of the book.. but at least she was mostly self aware? Had it not been for some of her selfish actions and often insufferable attitude, I think this would have been an easy 5 stars for me.
But Sebastian Flynn… 🫠 The amount of power and influence and darkness, while still being so insightful and caring and… possessive. I was obsessed.
Not only him, but a whole crew of characters I couldn’t help but fall in love with.

This book definitely could’ve used some additional editing and refinement, but I’m telling you - the next time The Sea Wraith makes port, sign me up. I need some deep sea adventures in my life.

[mei_li_terature · Rating 4 out of 5]

4.5 ⭐️

I am so mad at that ending 😭 I NEED BOOK TWO ASAP

[Katie Butterworth · Rating 5 out of 5]

This was a captivating read!! I’m glad I picked this up because I am obsessed!

[Megan Dobberteen · Rating 4 out of 5]

4.25⭐️’s - i need to read more treasure hunting books.

[Ali Gallagher · Rating 5 out of 5]

Yes yes yes. I had a feeling this would be good, and it did not disappoint. Bridgerton meets pirates of the Caribbean 💯 🔥
I honestly don’t have any complaints. It was easy to follow and digest and kept me gripped throughout. I couldn’t put it down! The MMC was 🤤.
I’m so glad the second book is already out 👏 Ekk!

[Kayla’s Book Binge · Rating 5 out of 5]

I need to calm down to be able to write the review. It’s a pirate masterpiece that I need everyone to read!! I loved every single thing about this book, but especially our possessive captain. This book had me screaming, sobbing, screaming again. I am already so attached all of these characters. It’s not even funny. Going on a pirate treasure hunt is so fun and gets your heart pumping. Throw in a possessive man, danger and an ex-fiancé trying to get you back and like I said, it’s a pirate masterpiece.

One of the things I loved is watching Rose progress from her sheltered, spoiled life to starting to embrace the freedom of the pirate life. She’s grown up in the Bridgerton-esque world of historical society where women have to conform. She is thrust into this pirate world where they are all completely different than the people she grew up around. She had an emotional abusive ex who has instilled all of these insecurities about who she is as a person so Rose’s character development throughout is so interesting to read about. In a lot of ways she does remind me of Elizabeth Swan and how at the start she had no idea how to be a pirate, but by the end she was born to do it. I hope throughout the series we get to see Rose let go and feel the freedom and find who she truly wants to be. By the end of this book it really sets the stage and I can’t wait to watch it unfold. I know a badass in the making when I see one!!

Of course I’m gonna talk about the romance because Captain Flynn can get it seven days a week and twice on Sunday. What can I say, a possessive man will do it for me every damn time. “I would find you in any life. The afterlife will be no different.” IM SORRY?!?! The things this man says, had me giggling and screaming so hard. He reminds me of that scene in Hercules when he is swimming in the underworld trying to get Meg’s soul back while it’s literally killing him. Because that is what Bash would do for Rose. He is down bad and I ate it up!

The creatures in this book are so interesting to read about and every interaction with them had my heart going a mile a minute. it feels like there’s more than meets the eye with these creatures and their connection. Absolutely Google what all of them look like whenever they get mentioned!!! Terrifying.

I cannot wait for book 2, I need it immediately after that ending!!!!!

Spoilers below:
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I knew the second we were introduced to Billy and his witty charismatic humor that he was doomed. The sweet funny side character always dies dammit! I prepared for it and it still fucking hurt. I was sobbing when he it happened. He was so funny and charming, he deserved to live dammit!!! I swear to all that is good that if anything happens to Dilly, I will lose my ever loving mind! She’s the sweet, kind, best friend so consider myself concerned for the future books!!! I also cannot get over that bash lost his arm. That was actually so crazy, that entire scene had me so stressed. I need some type of magic to happen so he can get his damn arm back.

I hope Rose actually does have some type of connection to these creatures so she can become a bad ass creature taming pirate. Just imagine If we get a scene in the next book of her rescuing him from being hanged!!!!

This series better end with her being a full on pirate, getting that tattoo, and sailing off with her hot captain.

[Cate · Rating 3 out of 5]

This book had some good potential but it only picked up around 75%. Yes it had the monsters and the pirates but it just was lacking that next level.
The mfc certainly was childish and at times it felt ridiculous. But the characters were all great and the ending was pretty good.
There were times when I felt like the author would jump from one thing to the next and I had no idea how we got there, like when she had been mourning her brother for a year? And then he was on the ship? I could have missed that detail being explained earlier and missed it…. It was just an ok read with nothing special.

[Sara Causer · Rating 5 out of 5]

If I could rate this 6 stars I would! I have read 100 books this year and this one is top of the list. I couldn't sleep, I could barely work. I could not put this down. The characters are heartfelt and endearing. I fell in love with Billy against all odds and he isn't even the MMC. Alth0ugh do not even get me started on the hunk of pirate goodness that is Sebastian Flynn. He is outranking all the book boyfriends.

"I went to the other side of the world to try and forget the way you tasted" --- Girl I had to fan myself!

And our FMC is all bravery and badass! She deserves a darn medal for not jumping Bash's bones on page one! And this line --- "If my flame ever dulled, he'd be the first to pour more coal into me," I said.

I love the freshness of Dilly and the overcast sky that is Inu. The dynamics of the whole crew made it feel believable and the feelings real.

I felt like I was on the voyage as well. The ending had me in tears! This book is an absolute master class in storytelling.

[Havok · Rating 5 out of 5]

I can't even begin to describe how adventurously funny Mysterious Fathoms Below was! Rose was an absolute breath of fresh air: resilient, hilarious, and incredibly strong. Her connection with Sebastian was filled with passionate laughter and heartfelt moments that made me root for them from the start.

The story was packed with action and adventure, blending new, imaginative places with familiar ones in such a creative way. What truly moved me was the bond between siblings and the powerful love of family that drove Rose to risk everything to save them. It was amazing to see such loyalty shine through, and the moments of betrayal only made it more impactful.

If you're into a wild mix of laughter, heart, and non stop adventure, I highly recommend this book. You won’t regret diving into these mysterious depths!

[Abbie Sharp · Rating 5 out of 5]

OMG...I can not WAIT for this physical copy to come out so I can buy it immediately and read it again!! Rose and Bash are EVERYTHING!! I fell in love with Rose from the very beginning and I was so committed to her journey. The story between Rose and Bash and the emotions in the relationship between Rose and Oscar kept me glued to the book, unable to put it down!! I became so invested in all of the characters in the crew and the ending was the perfect way to leave us wanting for the next book!! Well done J.A. Good!

[Veronica Perez · Rating 5 out of 5]

Mysterious Fathoms Below is an absolutely wonderful pirate romantasy with Bridgerton meets Pirates of the Caribbean vibes. it's truly a unique blend that hits all the right tropes for lovers of the genre! Reading it was a breath of fresh air. The pacing is fantastic, and the storyline is so compelling. What's more is we have a FMC who stands apart from the same old, same old. Rose is neurodivergent and has a knack for saving herself (with the help of a very trusty paddle!). The lore is rich and immersive and not only are the FMC and MMC great, but I enjoyed all of the side characters as well! 10/10 read. I'm already hyped for book two!

[Ashley Gregory · Rating 4 out of 5]

4.25 ⭐️ Someone said this book was Bridgerton meets Pirates of the Caribbean and that was so accurate. This book exceeded my expectations. After that ending, I’m devastated that I will have to wait an undisclosed amount of time for book 2 ❤️‍🩹

[~Ashley~ · Rating 3 out of 5]

The first half of the book was a slowwww burn....I found myself waiting for something to really hook me. But I held on, hoping it would pick up, and I’m so glad I did. Once it hit its stride, it delivered. The second half was packed with intensity: lust, heartbreak, and moments of raw, emotional beauty that made the earlier pacing feel worth it. There were scenes that absolutely consumed me.

That said, the ending left me... underwhelmed to say the least. It didn’t quite land with the same impact as the buildup deserved, which has me torn on whether I’ll continue with the next book when it's released. Still, I can’t deny how much the middle of the story pulled me in.

[Marie · Rating 5 out of 5]

I honestly don’t know where I found this book or how it was added to my tbr, but I am so glad that’s where it landed and I pushed it to the top of my pile. What a ride!!! Pirates life for me! Yes please! Never, not once, was there a dull moment. Loved the quirky little family that was made out of a crew of mismatched people, all different backgrounds and history. Billie was just a highlight side character. How Rose was with her siblings was spot on, they loved and bantered as expected. Flynn was sexy in an emotionally mature way that makes readers swoon. I want to be Dilly’s bestie! Strong story. Strong characters. Just an exceptional read!

[Heather Young · Rating 5 out of 5]

Ok, imagine sitting at the end of the pier with the sun on your face and a salty sea breeze in your hair while you swing your feet and squeal in delight. That is what this story makes me feel and I cant shut up about it!

This was such a fun time! Perfect summer vibe read🌊Think Bridgerton mixed with Pirates of the Caribbean. The FMC does a lovely job of representing navigating relationship as a Neurodivergent young woman😍 The MMC will make you swoon. There is AMAZING banter and found family and mysterious sea monsters and and and…. Such a freaking breath of fresh air❤️

[Christina Mares · Rating 5 out of 5]

Pirates, mysterious creatures, treasure & romance… need I say more! This follows Rose who teams up with the Captain of the Wraith to save her family from ruin and herself from an unwanted marriage. It is complete with lovable characters and a swoon worthy possessive pirate captain. If you liked books like The Ever King you need to add this to your TBR now.

Thank you for this wonderful ARC by J.A Good

[Taylor · Rating 5 out of 5]

this was actually so surprising, really really enjoyed it! The world building was done well and all the characters were super interesting. gimme the next one! also the playlist provided has me vibing hard and was fun to listen to while reading, highly recommend !

[Janneke RS · Rating 5 out of 5]

Pirates,mysterious creatures, a treasure that awaits...I loved it!
The main character knows herself, and at the same time not.
The tension, the plot, it just has everything! And I just need book two like yesterday? Please give me more!!!

[Heather Burke · Rating 4 out of 5]

The writing was just a tad clunky in some places, but it could have been me. I really enjoyed it!

[Elle Clayton · Rating 5 out of 5]

Loved the adventure in this book, it was refreshing to read a fantasy that isn’t about fae. Would have liked a little more world building but hoping the next book with deliver more

[Whitney Abbott · Rating 5 out of 5]

5⭐️ I loved this book so much !!! Can’t wait for book 2

[Carola · Rating 4 out of 5]

4,25*

[Brenna Bickel]

Pirates of the Caribbean meets Bridgerton… the reviews were correct. I enjoyed this 😅