
Member Reviews

I could not get into this book for the life of me. I was just so bored I had to DNF
Thank you to the publisher for the advanced copy

This book is an epistolary novel written in the form of letters (pst-that’s what epistolary means) between four characters who live on a planet that is almost completely covered by vast oceans, although we occasionally see input from others throughout the novel. There are also two main timelines: the recent past and the present. In the past, Sophy is leaving for a deep sea expedition while her sister, E. remains in their unusual underwater house, called Deep House. While alone at the house, E. begins writing to Henerey, a scholar, and their relationship blossoms over the course of the book. In the present, Sophy begins a correspondence with Henerey’s brother Vyerin, through mutual grief; Henerey and E. have disappeared and are presumed dead. The circumstances, however, are a mystery that Sophy and Vyerin hope to piece together through shared letters from the past.
I would recommend this for those who love English classics, fantasy, and the Emily Wilde novels. The language is very flowery and circuitous; the tone of the letters, particularly in the beginning, is very formal and reminiscent of Victorian prose. The characters speak to each other from a frame of reference which they already knows as a fully realized world but that we arrive at by glimpses. I rated this book highly as it is a very unique novel, and the world is fascinating. I loved watching the story unfurl. The story really picks up partway through, however I took away one star because I found the beginning to be a little bit plodding and difficult to get into. I could see some people DNFing in the first few chapters if they don’t appreciate the prose.

Dear reader,
This was not for me. I swore up and down it would be, but I felt like it was Emily Dickinson trying to hard and that’s a pass for me. So reader, it’s a no. For me, respectfully.
I tried really hard with this one. I really did. Unfortunately, it did not work for me. It would be rude and a disservice to rate this as I know several others really enjoyed it.
It is not for me and I had to DNF (did not finish) for reading reasons. I could not connect with the plot of the characters at all. I did not and could not force myself to read it as I picked it up and put it down several times, but could not get into the book.
I appreciate the opportunity, but it is not going to be one I will recommend going forward.
Thank you again for my gifted copy.

DNF at 50%
I tried really hard to push my way through this book. It's compared to TJ Klune's whimsical stories like House in the Cerulean Sea which is one of my favorite cozy reads. However, this book in all honesty is dry. There is a little bit of whimsy written into the story, but the story itself couldn't keep me compelled. You follow correspondences between two people (Sophy and Vyerin) who have recently lost their siblings ( E. and Henerey) in a tragic accident. Sophy and Vyerin find letters from E. and Henerey that tell of how they grew close to one another, and for closure Sophy and Vyerin send each other these letters. Through this correspondence Sophy and Vyerin grow close and tell each other about their own lives. I'm sure there are people who will love this book, but sadly this story just wasn't for me.
Thank you Netgalley for the ARC from Orbit Books

- book review -
A Letter to the Luminous Deep by Sylvie Cathrall takes place in an atmospheric underwater world full of rich detail and interesting characters. The book is told through letters and the correspondence between two characters who meet after their siblings both disappear and want to understand more of their relationship before their disappearance. Part fantasy, part mystery, part romance - this book is a slow burn and can take a while to get through, but the writing is very poetic and beautiful. I enjoyed it!
3.75/5⭐

This is an epistolary novel and I think it would have been much stronger if it wasn’t. Epistolary novels have their own strengths and weaknesses. A desire to repeat conversations with people other than the recipient of the letter is not one of them and makes no sense in an actual letter writing. Also, some of the topics that are discussed feel forced and only that the author needed the reader to know the information. Anyway, it is a lovely written book but very slow. One reviewer said the entire book was basically a prologue, and that is somewhat correct. The plot starts around 80% into the book and a second book is needed to solve the main mystery of the book. I would recommend the second book not be entirely epistolary, but I am unlikely to read it either way. Also, this is a pseudo-Victorian, water covered world without the prejudices of the period in our world but still some of the cultural hallmarks, which can be a bit confusing when combined with certain levels of technology and medicine. The romance is sweet and very quiet. In summary, potential readers should expect a very quiet book with pen pals about an undersea mystery that is not solved in the first book.

Blog Post goes live May 14th
Imgur link goes to Instagram graphic scheduled for May 12th
(I also bought a copy so it'll definitely be featured in physical form on the instagram)
Will be discussed on Youtube's May Reads pt 1
Amazon Review submitted, pending system approval
TL;DR: While I can see this not working for everyone as it’s entirely letters and notes - but I adored this. So beautiful and engaging!
Source: Netgalley - thank you to the publisher! I did also buy my own copy I loved it so much.
Plot: This (through letters) tells the story of Sophy and Vyerin as they figure out the lives of their missing siblings E. and Henerey before they were lost in a tragic explosion.
Characters: We really do get a good feeling for these characters, even through these notes and letters. I felt like I genuinely knew them and they linger in my head rent free.
Setting: So much was underwater! The whole world is based in an aquatic setting, ether on or IN the water. So cool!
Romance: The romance was actually the weakest part for me, BUT the platonic friendship that Sophy and Vyerin struck up was absolutely lovely and I think a highlight for me.
Thoughts:
I had such a blast with this one. This story is told entirely through letters and notes, and follows Sophy and Vyerin as they attempt to track their missing siblings last year of life. E. and Henerey, the siblings in question, struck up a friendship and then romantic relationship the year prior and on a in person meeting in Sophy and E.’s childhood home were lost when the home in question was destroyed in a seaquake. Now through the worst of the grief the two siblings begin to read the letters E. and Henerey share back and forth, and also exchange their own notes and letters.
Once you get used to the way we slide between letters (and you do need to read the headings to check who is writing and when) this story is a joy. In the current era we see Sophy and Vyerin slowly become tight and wonderful friends, a development I loved more than almost anything else in this. While in the past we see E. and Henerey fall in love, but primarily we explore the world itself which is delightful. Once a world in which the peoples dwelled in in the sky, now everyone lives on or in the water. We glimpse the history of the world and see what might be hiding beneath the surface in a set of surprising twists toward the end of the book.
I highly recommend this for fans of epistolary novels, especially those who like quirky or cozy feeling books. This has those lovely vibes and honestly left me with such a big smile. I had to order my own copy for my shelves and I cannot wait for the next in the series.
5 out of 5 bioluminescent nautilus

ARC Review: Publish Date 4/25/2024
Thank you Net Galley for letting me read more books!
This is an epistolary novel set in underwater academia (mostly) with fantastical elements. The title, cover art, and premise are gorgeous and hooked me immediately. The story very slowly unfolds across letters and time through a small cast of characters, and as we are with each character’s letter, we are learning about the very different underwater world that our loves currently dwell in. I will say again, the story, VERY SLOWLY, unfolds. This is not an action packed, fast paced book. It meanders. But in it’s meander, is a beautiful story of love, acceptance, and adventure.
The real stand out for me were the letters between our lovers, Henery and E! Their nerdy, careful, scholarly driven love and full acceptance of each other’s “quirks” (mental illnesses) was swoon worthy and refreshingly romantic. It is sweet, and honest, and slow, and gentle. I loved it.
It was not what I was expecting at all and it took me until about the 40% mark to be invested, but I was happily surprised and touched.
*THIS IS BOOK ONE (I didn’t realize that it was an intended series going in and was quite disappointed at the ending, but I blame myself for that)
4 stars

I hesitate to describe "A Letter to the Luminous Deep" as "luminous", because it feels trite, but this book was lush, cozy, mysterious, and so so charming. It's one of those books where I'm almost sad that I read it as an ARC, because the next installment is nowhere in sight.
I'm generally a big fan of epistolary novels. This was the first book that I read in awhile that was a true epistolary, as in 100% of the book was told in letters with no intervening narration. I think some readers will struggle with this, it slows the plot and the writing style is very unique. However, I was a big fan of the writing style and the format. I loved seeing how the relationships between characters blossomed through letters, both in the past and the present. I also found the writing style quirky and charming. It really helped set the vibe of the book.
The world of "Letter to the Luminous Deep" was so creative and well imagined. I loved both slowly learning about the culture of the world and unfolding its mysteries as the characters solved puzzles themselves. I think that the first book will act as exposition in a lot of ways, and I'm excited to learn more about the world and those who inhabit it.
I adored (almost) all the characters in the book, and the romance was utterly charming. I think this was a massively successful and creative take on this genre (light academia fantasy with romance) and I'm so looking forward to future installments.
4.5 stars
Thank you NetGalley and Orbit for the eARC. All opinions are my own.

4/5✨
A Letter to the Luminous Deep
I’m not going to lie, this was extremely hard to follow. Yet, I found the stories quite charming and I was sucked in.
The book is a combination of letters between multiple characters tracking time in the past and present. The first set from E and Henerey in the past before their disappearance. The second set between E’s sister and Henerey’s brother in the present, a year after they disappeared. Along with little glimpses into other scholars learnings.
The landscape is underwater, between dwellings/spheres and the surface.
It’s quite beautifully written and gives me Emily Wildes & Divine Rivals vibes. I’m looking forward to the next installment in this series.

Before you start reading my review, I want you to know this was a did not finish for me.
I first picked the book because of its cover. But then when I read what it was about it sounded like it would be a grand adventure type book and I was so excited.
This was not the case. The whole book is done in letter form(which isn’t a favorite of mine to begin with) but I was bored, it read like a scholar wrote it for a school project. Definitely wasn’t for me and I was sad that it wasn’t. Such a beautiful cover.

This one takes a little while to get into but I feel like people are giving up on it too early 😭.
It’s an underwater epistolary fantasy! Come on people. This is what good novels are made of.
The romance is compelling and the writing is beautiful. It’s a slower pace but it felt intentional. I.e. reminiscent to writing back and forth and the waiting that comes with it.
Be warned. It does end on a cliffhanger. I can’t wait to get my hands on the next one.

This story has truly captured my heart! From the very beginning, the intricate and expansive worldbuilding grabbed my attention and held it tight. The letters exchanged between characters, especially those between E and Henery, were particularly captivating. Witnessing their relationship evolve felt like a privilege, with the palpable tension keeping me on the edge of my seat. Even when E shared her innermost thoughts about Henery with her sister Sophy, it felt like I was being let in on their intimate secrets.
The premise of two scholars—one submerged beneath the ocean, the other above—investigating a mysterious phenomenon and falling in love before disappearing is not just intriguing, it's what propels us into the lives of their bewildered family members left behind, all grappling to unravel the enigma.
Though the story occasionally meanders, particularly when explaining the abundance of letters, the puzzle it presents keeps you engaged, the romances feel genuine, and the mysteries keep you guessing. What truly stood out to me was the format—a delightful epistolary narrative brimming with sweetness, romance, intimacy, and warmth. Not only do we dive into the correspondence between the main characters, but we also glimpse into the lives of their siblings, whose stories ended abruptly and mysteriously, offering a multifaceted view of the world through this unique format.
The setting is another highlight—a fantastical world predominantly existing on the water's surface, with three distinct areas, each possessing its own quirks and customs. It's a magical, vivid, and enthralling world, albeit with a touch of trepidation. The romance subplot was particularly compelling, with tender exchanges and a Slow Burn/Academic Romance dynamic that hit all the right notes. The mystery woven into the narrative was equally compelling and expertly crafted.
As the first installment in The Sunken Archive series, "A Letter to the Luminous Deep" lays the foundation for a richly developed world brimming with mystery, heartache, and love. Sylvie Cathrall's immersive storytelling, combined with the gradual unveiling of the lore, keeps you spellbound as you join Sophy and Vyerin on their quest for answers. This book demands to be savored, with its slow-paced narrative inviting readers to luxuriate in its intricacies. Though it took some time to adjust to the unconventional storytelling format, I soon found myself eagerly anticipating each twist and turn.
Consider this book as a 'set up story,' setting the stage for future installments in The Sunken Archive series. The focus on character relationships, particularly E and Henerey's blossoming romance and Sophy and Vyerin's poignant partnership, adds depth to the narrative, making it both heartwarming and heartbreaking. The realistic portrayal of mental health struggles adds another layer of depth to the characters. The bond between E and Sophy serves as the emotional anchor of the story, while Sophy and Vyerin's budding friendship showcases the healing power of companionship amidst grief. Even characters like Arvist, though occasionally abrasive, intrigue with their complexities and potential for growth.
A Letter to the Luminous Deep offers a mesmerizing blend of fantasy, mystery, and romance, underscored by its richly drawn characters and evocative storytelling. If you're ready for an enchanting journey beneath the waves, this book is your ticket to adventure!

This book was such an interesting layout. I thoroughly enjoyed the story, pacing, setting and characters!

A beautiful discovery outside the window of her underwater home prompts the reclusive E. to begin a correspondence with renowned scholar Henerey Clel. The letters they share are filled with passion, at first for their mutual interests, and then, inevitably, for each other.
I'm pretty new to the academic romance genre, but I am absolutely loving that it is told entirely in letters. A Letter to the Luminous Deep instills a quest for the truth, while providing insight into both the past and the present. Including discussions around mental health, academia, and scientific exploration, this magical underwater adventure leaves plenty to investigate. A wonderfully curious debut that completely enraptured me!

Thank you NetGalley for providing me a review copy, although I did purchase and listen to the audiobook.
This review is really interesting because I probably would never have purchased this book m, simply because it’s written entirely as an epistolary work. That said, I think it works really well for this novel, in ways that these types of novels usually don’t.
Other than that, this novel was wonderful. The characters are beautiful, their journeys together are incredible, and it feels primarily to be an exploration of love (in all forms.) I truly enjoyed it. (The audiobook in particular.)
So why only four stars? This book should not have ended where it did. It feels like it’s ending right where the story is beginning, gearing up for the next book. But we need to bring back door stoppers for situations like these. The journey though this novel was so good, but the plot didn’t really start to pick up until around the 50% mark, and it feels as though the book ended right before the natural climax for book one. The timing feels all off.
Still, I eagerly await the next book, and I would recommend this one. (Although maybe wait until you can pick up the next book.)

Thank you, NetGalley for this eARC in exchange for my honest review.
Going into this, I was expecting some whimsical and fun, as underwater fantasy isn't something I read a lot of, or find. But, this just didn't hit the mark for me. I was quite bored. This is cozy if cozy means slow-paced. I had to put this book down multiple times and fight myself to pick it back up. This may be great for some people, but it just wasn't for me.

Since reading EMILY WILDE a couple of years ago, I had been looking for any book that scratches that particular epistolary fantasy itch and none have ever come close to giving me the same feelings…until this book. A LETTER TO THE LUMINOUS DEEP is magical, haunting, and a quiet slow burn of a novel that builds and builds. I cannot wait to read more from this author because this so quickly became such a favorite for me.

(3/5 stars) I'm sure this book is for some people, but it wasn't for me. I was hoping this would be along the same lines as Emily Wilde but it just fell a bit short for me. Perhaps it was the format of the book (using solely letters) combined with the fact that there were multiple voices that all sounded too similar?

3 stars
This book is written in letters from the different time periods. It was hard to follow. I didn't hate it but I didn't love it either. It was just ok for me. I still don't know if I know what exactly happened lol.
Thank you to NetGalley and Orbit books for the opportunity to read this book.