For me this book almost took off too fast, I was left starting the book feeling confused and never really stopped. I read complex worlds regularly and enjoy them and even enjoyed the fact that this story was told through letters but it felt disconnected to me as a whole.

I was completely blown away by this book. The plot was enthralling and had me hooked from beginning to end, eagerly turning the pages. The author's masterful use of tone added even more complexity to an already gripping storyline, creating a truly immersive reading experience. I cannot praise this book enough - it is a must-read for any reader.

★★★★★ - 𝐛𝐨𝐨𝐤 𝐫𝐞𝐯𝐢𝐞𝐰

A Letter to the Luminous Deep by Sylvie Cathrall
༘Spoiler free ༘
⭐️4.25/5
Fantasy, Historical, Romance, Epistolary Novel
Multi POV
➳ 📓 Academia
➳ 🪸 Underwater World
➳ 💌 Pen Pals / Epistolary Romance
➳ 🫶 Mental Health Rep
➳ 👯‍♀️ Sibling/Sisterly Bonds
➳ ❤️‍🩹 Grief & Loss
➳ 🕯️Cosy Fantasy
➳ 🔎 Hidden Discoveries

✨ “Is not everything we accomplish but one small step in the Greatest Project of our lives – that which we do not complete until we pass from this world?“ ✨
My first foray into *fully* epistolary novels, such a deeply gratifying journey. This story truly grew on me, the intricate and extensive worldbuilding is what captured my attention and kept me reading in the beginning. If you’re used to binge reading, you may feel that the pacing of this book takes some adjustment. While i loved the platonic letters between characters, I found that the letters that drew me in most were between E and Henery. Watching their relationship blossom, was a gift and I truly felt the nervous tension between them as if it were my own. I found myself giddy when E would write to her sister Sophy about Henery as well. It felt a bit as if I were Sophy and E’s unnoficial sister, being filled in on their secrets.

Around 40% in, the correspondence between E & Henery really tugged at my heart and had me fully invested. By the end I was positively ready to pack my bags and join the characters down in the Luminous Deep. I look forward to the quest to come in the second novel.

This book is meant to be savoured, letter by letter. I think for my reread i will break down which letters to read each day to better capture the mood of this novel. I will post my updated letter reading schedule in the future.

❧✧･ﾟ: *✧･ﾟ:*❦*:･ﾟ✧*:･ﾟ✧❧

**Fantasy Scoring**
Worldbuilding ➷ ✅ 4.5/5
Foreshadowing ➷ ✅ 4/5
Plot ➷ ✅ 4/5
Relationships ➷ ✅ 4.5/5

Thank you to the Sylvie Cathrall, Orbit and NetGalley for the opportunity to provide my honest opinion on the ARC of this book.

Sci-fi is not my favorite genre by any means, but I was really looking forward to this one because it seemed to be a bit more fantastical and easygoing. Unfortunately, it still wasn't for me. Honestly, it may not even be considered a sci-fi, but it took place in the ocean with excursions and ships and stuff, so I really don't know. Anyway! I liked the writing style, but it didn't seem to fit the letter format of the story; it was extravagant, if you will, with lots of big words that didn't seem natural considering the characters are writing to each other. There was also a lot of diversity and discussion of mental health, which was good to see. It started out interesting because there is a bit of a mystery as to where E and Henerey disappeared to, but (getting into the things I didn't like), it drug on. and. on. About 60% of the way through, I was thinking to myself, "I've read over 200 pages of people writing back and forth about nothing." Now, to be fair, I like action and a faster-moving plot, so if you like slower fantasies, this may be more your speed (pun intended). I think this will probably be a hit for a lot of people, but for me, the pacing and the lack of a true plot until the last (literally) 8% of the book didn't do it for me.

This was quite an interesting book. The undersea academic setting was unique, and the imagery was beautiful; the story telling was done completely through reading material shared between characters. They all seemed to have the same enthusiastic, pretentious yet self-deprecating, slightly humorous voice – while very charming, it probably would have worked better if not applied to everyone. This was a cozy underwater mystery, so there was not a lot of action especially in the first half or so. I will say that the ending was a cliffhanger that left me frustrated, which means I’ve fallen right into the author’s plans and will read the next one when it is released!

Thank you to Orbit Books and Sylvie Cathrall for this ARC received through NetGalley.

Thank you to NetGalley and Orbit Books for this arc in exchange for an honest review!

This novel was enchanting. I will say that it’s a very slow burn. I took my time reading this because it’s a book meant more for savoring the world-building and character development. Initially, I was a little annoyed that there seemed to be much more of a focus on the friendship between Sophy and Vyerin than the relationship between E. And Henerey. However, as the story progresses, you see how the two are very much intertwined.

One complaint I have, which I think I have with most epistolary novels, is the sometimes contrived ways the author has to impart information through written correspondence. She does poke fun at this at one point, which did lessen my irritation a little.

While I did know this was first in a series, I did not realize this would end on a cliffhanger. I’m not sure how I’ll be able to wait to find out what happens.

Lastly, Vincenbras is one of the funniest characters ever.

<i>A Letter to the Luminous Deep</i> was a wonder to read (truly remarkable if you will). This book tells a story of sibling love, adventure, overcoming fears, and of course, falling in love. Set in a fantastical world where the ocean is the only thing these people know, we venture far beyond that. This story is told through letters, post missives, journal entries, and just about anything that can be written on paper.

This story technically begins far after, and provides a look into the past. After the disappearance of E. Cidnosin and Henerey Clel, E.’s sister and Henerey’s brother look for closure through the archival of their siblings letters, and they discover much more than they were originally anticipating. These characters are exceptionally charming and are all so unique in terms of their characteristics and actions. They are so fully fledged out even though we never truly see their actions. When I started this book I had no clue what “epistolary” meant, and it worried me at first, but I was pleasantly surprised by the amount of emotion and character that was portrayed.

I also look back and think about how much work must have gone into planning and writing this book. We follow multiple different extensive conversations via letters along with additions and journal entries all placed in a way that makes the story flow beautifully. That being said, this book definitely fits into a more “cozy” category, meaning that it’s slower and not very action-packed which I know is not everyone’s cup of tea, but I was so immersed in this world and these characters that I really didn’t mind.

Overall, this book is a beautiful fantasy that encapsulates grief and love and loss all in a wonderfully fantastical and queer-normative world! I really can’t wait to see where this series takes us!

Really enjoyed this book and the characters in it, however it was a bit hard to always follow who was “talking” as the characters’ voices and language seemed so fairly similar. That said, the story of E. and Henerey and this underwater world was very intriguing and I cannot wait to read the sequel.

I just reviewed A Letter to the Luminous Deep by Sylvie Cathrall. #ALettertotheLuminousDeep #NetGalley

E. is the reclusive middle child of a famous scholar who lives in an underwater house. When E. observes fish behaving oddly, she timidly reaches out to famous fish life scholar Henerey Clel. The two begin a correspondence that gradually blossoms into a romance. Then, a terrible explosion sends the underwater house into the depths and both E. and Henerey vanish. A year later, E's sister Sophy, and Henerey's brother Vyerin piece together their siblings connection through the remaining letters, sketches and paraphernalia. This book is an epistolary (in the form of letters) tale, which I've always loved due to the intimate feel of the prose. I always feel like I'm watching right over someone's shoulder. The world that these people exist in is whimsical and fantastic (and queer normative!), full of scholars of strange arts and lives spent mostly underwater. It took me a little while to steady myself in the universe of the story, but once I figured out the, er, currents, I was able to navigate with ease. Really the only complaint I have is that now I have to wait even more time for the second book in this duology. Give to ocean-loving readers who liked Emily Wilde's Encyclopaedia of Faeries by Heather Fawcett.

The idea of the book was really good. However, it didn't come off quite right for me. I don't mind epistolary novels, but this one didn't work for me.

I thought the concept of this was cool. I like the ideas of the letters going back and forth, I was very interested becuase of the underwater world. I really like books that are set up in the academia type worlds. So that did hit the spot there. In the end I did find it hard for me to jut sit back and relax and enjoy it the way I was hoping to. It could have also just been the time in which I was reading the book as well. I was looking for something a little more fast past and this is definitely the opposite. If you are down for a slow burn and a more cozier setting than this might hit the spot for you! I will say that now that I know what I am getting into I am hoping to reread this in the future and I think at that time it will hit better in my rating scale at then time. Until that time I will give it a 3.5 and will wait for my reread!!!!

I made two attempts to read this book. Initially, I believed that my inability to engage with the text was due to my personal circumstances. However, upon revisiting the book, I realized that I was unable to complete it due to difficulties with the writing style. Although I recognize that this book may have broad appeal, I personally struggled with its composition. I have rated it a three, attributing my rating to my own preferences rather than the author's skill.

I tried this one this because I often love underwater fantasy. However this was just didn't work for me. It was too cute and romance heavy for my personal preferences. My main issue was the narrative format was done all in letter formats. Sometimes that style can work but I found it to be a passive, dry narrative choice.

I requested this one because it might be an upcoming title I would like to review on my Youtube Channel. However, after reading the first several chapters I have determined that this book does not suit my tastes. So I decided to DNF this one.

DNF. I regret listening to the people who said this was like Emily Wilde, because that is a vastly unfair comparison. It is not. They're both epistolary and that's it. The problem with Cathrall's debut is that there are half-dozen letter writers and they ALL SOUND THE SAME. No distinctive voice. I can't continue reading this because it is literally headache-inducing. I am sure there is someone who will love this book, but I am not the correct audience.

I really really wanted to like this but alas I did not. While the idea was great the execution fell flat for me. It was very formal writing for me to really escape into. Written in letters or other types of writing entries two people come together to try and understand what happened to their family members. I wish that we could have explored the under water scene more.
Thank you NetGally! #ALettertotheLuminousDeep #NetGalley

Unfortunately, I DNF'd A Letter to the Luminous Deep approximately 15% of the way in. The writing style and the back and forth of the letters made it hard for me to feel engaged and I couldn't keep clear who the various letter writers/characters were and the plot. I had high hopes (epistolary, underwater, what else could I have asked for?!) and am sad that it didn't click for me.

Thanks to Orbit and NetGalley for providing an advanced copy!

I LOVE this book. Beautifully written. Read it in one day. Definitely worth reading. Highly going to recommend this to everyone

This novel was so beautifully written and thoughtfully crafted, I could not believe it was a debut! The voice of the narrative drew me in, and I loved the way the siblings all wrote to each other such that they sounded like they'd really grown up with each other (and each other's quirks). Going into it, I somehow didn't realize it would be a secondary world fantasy, but I found the invented world delightful. The build was slow and perfectly tantalizing-- I genuinely wanted to know more about their fantastical ocean and the research they were doing. I would recommend this to fans of cozy fantasy romances such as Emily Wilde's Encyclopaedia of Faeries or The Undertaking of Hart and Mercy.

In the end, however, this was not the right book for me. When I pick up a cozy fantasy, I do so because I want a light, easy read. The narrative structure here had one too many convolutions for me to freely enjoy it. It was 100% epistolary, which in itself is a small hurdle, and there was a whole web of letter-writers rather than a primary pair like I expected. Additionally, not all letters are in chronological order and we jump places and plots as we switch from correspondent to correspondent. Things did not begin to tie together as early as I had hoped. The work required to read it prevented me from fully immersing myself in the exquisite world the author gradually unfurled for readers.

Thank you to NetGalley and Orbit for an eARC of this book!

This book was so interesting and unique. There was a lot of development that made this book fascinating. The worldbuilding was probably my favorite part - I've never read a book that really develops an underwater setting for an entire book, instead of just a scene or two. The idea of underwater architecture, exploration, and more was really well-researched and well-executed. The fact that I was able to understand such a unique setting in an epistolary novel is even more impressive, as most of the reader's understanding comes from the letters and excerpts that make up the entire story. I do think that this book would benefit with some kind of glossary, though - since this is an epistolary work, some aspects of the science and setting were a little vague and would be better fleshed-out in a glossary, footnotes, or even some sort of excerpt from a history book to go alongside the letters and articles.
I also really liked the characters, of which there was a diverse cast. The author did a nice job developing the characters within the story, so it was easy to get an idea of each person's individual personality through those letters and messages. However, there wasn't a lot of variety within the writing. Each letter was extremely formal, and the characters didn't have a lot of individuality within their voices. If it wasn't for the headings at the beginning of each letter, there wouldn't really be a way for me to tell the difference between who is writing/speaking.
The romance between E. and Henerey was really sweet, and I loved the mental health discussions that took place between them (and other characters).
Overall, I really enjoyed this book because of its unique setting and storyline. Certain parts of the book were genuinely unsettling in the best way possible. I can't wait to read the sequel!

Thank you so much to Netgalley and Orbit publishing for providing me with a digital ARC of this book!

“P.S. Can’t believe E. started this whole thing by sending him a letter out of the blue. He loved that, I’m sure. He also loved her - even surer.” ⭐️⭐️⭐️⭐️💫

A Letter to the Luminous Deep is a whimsical epistolary fantasy set in a mystical underwater world with an ominous secret. It is a very unique style - and for me - it’s one that I loved. It was so cozy and romantic, yet also dark, mysterious and suspenseful.

Through a series of letters, sketches, field notes, and journal entries, the story follows two grieving siblings, Sophy and Vyerin, as they connect and piece together the last year of their respective siblings’ lives, their love story, and the tragedy that befell them.

From reading the romantic prose of E. and Henerey’s lettters to Sophy’s reports from the Deep, we can see something ominous is lurking just out of sight. Something that will change all of their lives forever.

Word of warning - it is book one in a new series. 👀

Thank you to Orbit Books and NetGalley for an advanced electronic copy in exchange for an honest review. A Letter to the Luminous Deep comes out on Tuesday, April 23rd.