This book was supposed to be like “Emily Wilde under water”. Emily Wilde was an absolute highlight. I loved it. It was cozy, fantastical, exciting and romantic. Being compared to it is a big compliment in my opinion and will raise my expectations quite high. Aside from that, I’m always down for books with anything water world, doesn't matter if it's about pirates, mermaids, other sea creatures, or whatever. So this book was a must.
And let’s be honest – the cover is stunning. It definitely played a huge part in me wanting to read this. Look at it. I’m in love with it.

Unfortunately, this book became one of the biggest disappointments of this year so far (at least when I read it, we were only two months in, so it could’ve been worse, but still. Huge disappointment.) It was neither cozy, nor fantastical, exciting or romantic or anything that I enjoyed about Emily Wilde.
Disclaimer – this review might be slightly strong worded. Don’t take it personally. I’ve got nothing against the author. If you did enjoy this book and get insulted by people having different opinions from your own, you might want to skip this review.

First things first – the plot. When E witnesses two strange sea creatures she doesn’t recognise, she contacts her idol, Scholar Henery, and they strike up a conversation.
Later, her sister Sophy takes up correspondence with his brother Vyerin, exchanging their siblings’ old letters to reconstruct their story – as both of them have gone missing.

What I expected: E and Henery exchange letters, theorising and researching about the strange fish, while talking about gorgeous underwater worlds and their passion for marine life, while Sophy and Vyerin piece together the letters and slowly figure out what happened to them (and maybe go on some kind of rescue mission). I did not expect a full-on thriller or anything like that – if it’s supposed to be like Emily Wilde, it’s gotta be cozy fantasy.

What I got was nothing like that. It does start with E and Henery exchanging letters – but after the first letter, they barely mention the sea creatures. Or other topics concerning the ocean. They talk about their siblings and what those are doing. They talk about their families. Their lives. Their history. Don’t get me wrong – all of that could be interesting. But it really really wasn’t. I couldn’t have cared less.
The same for Sophy’s and V’s letters. You’d think they’d look for anything interesting or strange inside those letters. But no. They talk about how adorable their siblings are. And what they did during that time. And what they are doing now. And none. Of. That. Is. Interesting.
Honestly – for basically 80 % of this book, nothing happens at all.
There are also letters from other people, some articles and other sources, but I honestly didn’t see the need for including any of those.
And the last couple of chapters didn’t make any sense to me. They were very rushed and kind of seemed as if the author had realised that she still needed a plot. At this point, I wasn’t sure whether this was supposed to be sci-fi, post-apocalyptic or fantasy, and the ending didn’t exactly clear that up. Nothing fit together.

I don’t even know how the second book is supposed to play out. The ending does set up a second book, but if it’s gonna be written in the same style as the first one – oh dear. Either Sylvie Cathrall speeds up everything fast, or she’s going to need ten books until anything happens.

Now if the book was full of beautiful descriptions of underwater worlds, I might not have cared about the lack of a plot. But I barely have any idea what this world is supposed to look like. The world building was honestly bad. Very vague. As I said, I don’t even know what kind of genre this is supposed to be. And considering that the whole thing started with the witnessing of strange, never-seen-before-creatures, I would’ve expected to actually read more about those creatures and just the underwater-world in general. Look at the cover! Doesn’t it promise gorgeous reefs, colourful fishes, and hidden secrets? But no.

Of course, the characters are mainly scholars, or at least very interested in the sciences, so you might not get any flowery descriptions.
Well, actually, all of them used extremely flowery language. Especially for scholars. It does get mentioned that Henery has an interesting style of writing his papers, but it simply didn’t fit. If he honestly writes his papers the same way as his letters, I really don’t understand how anyone takes him or his research seriously. He’s a scientist. He’s supposed to talk about science. Not about his emotions and dreams. And while he puts very flowery language in every single piece of writing, he still doesn’t manage to describe the setting! All of it seemed to exist simply for the purpose of making this book longer. The whole story could’ve easily been cut down by two thirds if the characters had decided to talk like human beings.
The way they spoke in their letters was simply extremely unnatural. No one talks like that. I would expect a certain number of scientific phrases, perhaps some eccentricities. But this was extreme. Both E and Henery wrote, as if they had never talked to another human being before. Every single one of their letters sounded like “Hello, fellow friend of water creatures. I have thoughts! I am smart and scholarly, look at me using smart and scholarly words while describing my thoughts! But oh, I’m also human, so here is something deeply personal about me. I apologize for oversharing, considering we've never met each other.”
Yes, it’s okay to have characters that are socially awkward, perhaps neurodivergent. But this was way over the top. It honestly read like robots trying to appear human. And they babbled so much. And then they apologised for babbling. And then they babbled some more. Also, for someone apparently so excited by this new scientific discovery, Henery changes the topic way too quickly. From the first letter on, it did not seem as if he was a scientist.

Are they at least interesting on their own? Not in the slightest. All the characters are exactly the same. They don’t seem to have any kind of personality at all. It went so far, that I honestly couldn’t keep them apart. The letters always said who was writing to whom, but once a letter went on for more than two pages, I honestly didn’t know anymore who was talking. Only when another character got mentioned, I managed to figure out what was going on. There were no differences in the tone or writing style at all.
This book is an epistolary novel. Of course there are certain difficulties with writing a book like this. But that is not an excuse. I’ve read multiple epistolary novels that were truly fantastic. If you encounter problems you cannot solve, either change the plot, or change the format. Not everyone can write a novel like this and that’s fine! But it would be better to write a good normal novel than a terrible novel that’s supposed to stand out by formatting. It’s gonna stand out in an entirely different way.
There was so much info dumping, which of course leads to me forgetting every single thing they said. Also – why do they explain the history of their world to each other? Apparently, everyone knows it, so why talk about it? Well, of course so that the stupid reader also knows it. But I hate things like that! Give me reality! I don’t randomly start spouting history facts when talking about my home or weird animals I saw. And there was way too much way too early.

The romance was weak and weird. Both Henery and E were very awkward, while being instantaneously infatuated with each other. There was no chemistry. They barely even seemed in love, it looked more like obsession to me. I didn’t get them at all.

Overall – the plot was boring. The world was barely described at all. The characters did not appear like human beings. The writing annoyed me very much.
Honestly, the best thing about this book was the cover.

Thank you, NetGalley and Little Brown Book Group UK for an ARC in exchange for an honest review.

A very beautifully written book. While the writing style didn't quite hit the mark for me, I can see many other readers enjoying this.

I finished A Letter to the Luminous Deep yesterday, and find myself in two minds about it.
An impossible book to classify, it is part mystery, part love story, part fantasy, but reads like a memoir or a journal due to the epistolary format.

I loved the mystery - we've reached the end of the book and there are so many tantalising answers held just out of reach - what caused the 'dive'? What is the thing that the Antepelagic feared badly enough to plot escapes routes for future descendents? Are they the same thing? Where did Henerey and E go? Are they safe, trapped, exploring? There are so many questions on the tip of discovery that I am compelled to search out an immediate release date for book 2, in the hopes that my curiosity will be quenched in the not too distant future!

But that said, I didn't, overall, love the book. I felt like there were many unnecessary interludes (Were they? Will some of them become more relevant in book 2?) with interjections from other books.
I also felt like we were missing a touch of worldbuilding. While some parts need to remain a mystery, as the history and purpose of the 'structure' become apparent, there are several things not explained. Letters seem to arrive remarkably quickly, in only a few hours, yet we hear of them travelling by boat, and presumably holding multiple letters to several destinations/recipients rather like our own postal system. With the speed of delivery, automated post (which I assume to be something like email, being real-time) seems largely unnecessary. The civilisation seems small, being only the survivors of the 'dive', but I can't determine how small, nor how far geographical locations are. It seems tiny, despite being years after the 'dive'. I can overlook these things, as the mystery and romance elements were so strong.

But, most importantly, we have four main characters, and letters/articles from at least four or five other smaller roles. And yet, I could rarely pick out a distinct voice. I needed to pay attention to the writer and recipient of each letter, and to the year, because the narrative voice was so similar in each that I didn't feel that there were distinct personalities at play. The things I know about these characters is because of the things they wrote, not the way in which they were written.
I am certain many people will love this book, and it is a truly stunning edition to add to the bookcase (the cover is most excellently done - beautiful but with hints of the collapse of Deep House). I, myself, will not be put off purchasing book 2 because the storyline was excellent and the mystery intriguing. I do feel that the execution was not my cup of tea, though, in this case.

I unfortunately had to dnf at 70ish% only because the epistolary form was not for me, and I really tried to get used to the form but it just didn’t click.

I did however loved everything else about the book: the worldbuilding was incredible and the writer’s prose only made it more beautiful. I was very moved by the fragility and brokenness of the characters and the love story was so touchîng. I really wish i were able to move past the form because the book had everything I love and I have no doubt it will find its readers because it completely deserves it.

Letters
⭐️⭐️⭐️
The book wasn’t for me. I didn’t vibe with it. I really wasn’t the target audience.
When I first saw the book I wanted to read it as it had been compared to Emily Wild series (although I wouldn’t compared them)

The writing was very poetic and flowery but with very little happening made it hard book focus and keep reading. Only the near ending kept me intrigued, it would have been better as a standalone rather than a series.

Thank you Orbit Books & Netgallery for the eARC

[ARC provided by NetGalley and Orbit. Thank you for the opportunity to read and review A Letter to the Luminous Deep.]

Rating: 4.5/5

What an unexpected gem of a read! Although it took me a moment to really get into this book, it wasn’t long before the epistolary narrative swept me away into a watery world of longing and mystery. It’s such a joy to fall in love with books that are so incredibly unique and yet still contain all the familiar tropes that I know and love. Set in an incredible oceanic setting, A Letter to the Luminous Deep is perfect if you’re trying to scratch that Emily Wilde itch, and its whimsical style along with some very charming characters will have you eagerly turning each page as you unravel this scholarly mystery.

This story follows Sophy (sister to E.), and Vyerin (brother to Henerey) as they try to uncover the truth behind their siblings’ disappearances. By revealing letters, sketches, journals, and field notes, they begin to piece together a timeline of events that is as shocking as it is intriguing, and that may change their world as they know it.

Admittedly, I was a little sceptical at the beginning of this book as I wasn’t sure how the emotions of each of these characters could be accurately conveyed – especially when there is a romance at the core of the story. Of course, I needn’t have worried, because this author expertly lays out one of the sweetest and most tender love stories that I’ve ever read. Sophy and Vyerin exchange letters that E. and Henerey had sent to each other before their disappearance, and the blossoming relationship between the pair is beautiful to watch unfold. From letters filled with longing to scribbled conversations on sheets of paper, I was always eager to get to their writing to see how their love was developing.

Another highlight of this story is the individual characters. Although they write in a similar style, their inner musings about the world around them is what truly sets them apart. I especially related to E. who struggled more than most with her own brain, and as someone who is prone to checking once, twice, three times and so on if something bad has happened or may be about to happen, I could empathise with this kind of thought process. The author does a great job of capturing what it’s like to live with conditions such as OCD as we often see E. battling with intrusive thoughts and compulsions, and I was rooting for her every time she stepped out of her comfort zone as I know all too well would have been incredibly difficult.

The setting is also mesmerising, and I was often caught in a daydream imagining the watery depths of the world shown to us in these letters. The charm of this world paired with the mystery of the plot was constantly keeping me on my toes and I felt like I was piecing together the truth much like Sophy and Vyerin as time went on.

I was saddened to reach the final page because I could have spent so much more time in this enchanting world searching for E. and Henerey. If you love academic mysteries that are heart-warmingly magical, this is a book you need to add to your list. I can’t wait to read the next instalment when it comes out!

I requested this book without knowing anything about it, which I think made it even more enjoyable. So I will try to tell you why I loved it while revealing as little as possible about the story.

It takes place in a different world, that is almost completely made out of oceans. We understand early on that Scholars are extremely important in this world, and most of the characters are either Scholars or Scholar's family members. It definitely makes A Letter to the Luminous Deep fit in the Academia genre, but I'm not sure if it's more light or dark academia.

The story is told in an unusual way, which I found it very enjoyable : it is told through the letters that the characters send each other, excerpts from their diaries, news articles, etc. These characters are exchanging letters because they are trying to solve a mystery, and I was so involved in the solving of the mystery as well. I wanted to know what had happened, how, why, everything !

I also loved how they talked about many other things in their letter. They told each other about their daily life, their family, their academic research. We also see some of them fall in love, it is so sweet ! It gave me the impression of being a Scholar of history myself, studying a far away civilisation through letters found by archeologists.

Unfortunately this was my first ever DNF at about 60%

I tried really, really hard to finish it since I abhor not finishing anything I’ve started. I had been excited to read it since I first received the ARC but I couldn’t get into it and simply was not enjoying reading at all.

Truthfully, I don’t think this style of book is for me. I don’t mind some letters in books, in fact often I enjoy them., yet it would appear that I find a true episotolary format frustrating. I just couldn’t find it in myself to care about these characters. Often, I found it confusing as to who was replying to what , who was writing when etc.

It’s a shame, it is well written. And I have no doubt a great many people will enjoy this. The Cover is stunning aswell.

Sadly, just not for me.

I do not post reviews on my platforms on books I don’t enjoy that I give below 3 stars and I feel it wouldn’t be fair since I didn’t finish the book. Therefore here on NetGalley is the only place I shall be reviewing.

Many thanks to little brown book uk and NetGalley for the Arc.

DNF @39%.
It pains me to say that this was a DNF. I tried, I really tried to care enough about these characters and the action to continue reading it. But I don't find myself reaching towards this book anymore. I don't like the writing, I can't remember the previous character when I start the new chapter. I really wanted to love it, but unfortunately, I do not. I love the cover and the premise, but it bore me.

Every so often you come across a book which stays with you long after you finish it. ‘A Letter to the Luminous Deep’ is one of these.
Set in a world made up of campuses and scholars, where nearly all land is manmade and history tell of their ancestors falling from cities in the sky, it tells the story of ‘E’ Cidnosin, a reclusive and anxious woman who lives in ‘The Deep House’ under the sea, and Henerey Clel, a renowned marine scholar. The story is set a year after the two have mysteriously vanished and their respective siblings are piecing together what happened to the pair. Told entirely through correspondence, this poetic, imaginative and rule breaking novel is beautifully written and heart-warming with a touch of mystery thrown in. Think Jules Verne meets Victorian pen pal romance.
It took me a little while to get used to the format of the book. Sophy and Vyerin (the missing pair’s siblings) send letters to each other and enclose correspondence sent by their missing siblings, so they can piece together their last days. It is a bit confusing to begin with and the language is very descriptive but pay attention to the titles and dates at the top of letters and it becomes such a joy to read! The act of writing a letter to someone is so personal that we get to know the characters private thoughts, fears, desires and experiences (if they care to share them) and learn more by what they don’t include! All the characters, and especially ‘E’ with her anxiety, become so real that they just leap off the page. The use of letters gives the story a sense of immediacy- we feel like we’re experiencing things as they do, and it makes it all the more real.
I absolutely loved the way we see the relationship develop between ‘E’ and Henerey, with its slowly unfurling romance and beautiful descriptive language! It harkens back to a time when romance was done properly.
If you like lots of fast action scenes, then this isn’t the book for you. But if you like slow burning and unfurling storylines, deep sea exploration and mysteries, blossoming romance and a touch of fantasy then read on. I was so happy to find it is the first of a new series. It is my favourite read of the year so far and I really look forward to the next one in 2025!

A Letter to the Luminous Deep was such a delight to read. It's a book written in a compilation of letters, journal entries and "e-mails" about the mystery of E. and Henerey's disappearance, in which a year later E's sister Sophy and Henerey's brother Vyerin decides to correspond and sends each other letters from their respective siblings to each other to discover what exactly happened to them - right from the beginning of their siblings' own correspondence.

I truly loved reading this book. It's cozy and "quiet", and everytime I pick this book up I feel like I'm reading from an old friend because of the formatting. If you're a fan of fast-paced fantasy then you'll probably be bored of this one but I love the slow moving of the plot and just being there to understand the characters. I loved reading E. and Henerey's romantic development through their letters because the love they have and the genuineness of their feelings really seeped into the pages that they wrote. I also loved E's character so much and the way this book handled topics of mental illness in a fantasy setting quite well. Another thing I love was that despite this book being about them both, I also really enjoyed reading the correspondence of Sophy and Vyerin.

Actual rating: 4.5

"A Letter to the Luminous Deep" is the first installment of "The Sunken Archive," a fantasy series written by Sylvie Cathrall, here at her debut. An epistolary novel, made entirely of letter exchanges and automated posts, supplemented with newspaper articles, recordings, journals and various documents. A spellbinding, delicate and intimate book, characterized by extremely charming and atmospheric world building, highly elegant and evocative prose and intense characters. A story that proceeds slow and placidly, taking its time, with no particular moments of action. A tale full of explanations and anecdotes, in some moments particularly dense, which from time to time gave me a feeling of heaviness. A magical, lyrical novel that captured me completely and left me eager to read the sequel!

Thank you to the Publisher and NetGalley for giving me an ARC of this book in exchange for an honest review.

This book has been on my radar since I first saw the cover months and months ago, and yet when I started reading it, I had somehow managed to not realise it was an epistolary novel despite the title… So I won’t let you get any further into my review without knowing what this magical debut is about.

A charming fantasy set in an underwater world with magical academia and a heartwarming penpal romance, perfect for fans of A Marvellous Light and Emily Wilde's Encyclopaedia of Faeries.

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.

Together, they uncover a mystery from the unknown depths, destined to transform the underwater world they both equally fear and love. But by no mere coincidence, a seaquake destroys E.'s home, and she and Henerey vanish.

A year later, E.'s sister Sophy, and Henerey's brother Vyerin, are left to solve the mystery of their siblings' disappearances with the letters, sketches and field notes left behind. As they uncover the wondrous love their siblings shared, Sophy and Vyerin learn the key to their disappearance - and what it could mean for life as they know it.

The comparison to Emily Wilde is completely spot on, and for me, it does what I wanted from the first Emily Wilde but didn’t quite get (I will be reading book two at some point and hopefully I get the delightful light academia that I’m looking for).

‘A Letter to the Luminous Deep’ has that suspended, ambiguous time period that could be the 1920s or the 40s, or it could equally be an alternative version of somewhere in the 19th Century. There’s a formality to the correspondence between E and Henerey at first, and again between Sophy and Vyerin, that only dissolves with time and intimacy and sometimes still creeps in at times. It’s charming and sweet, slow and full of that suppressed yearning that I associate with historical novels and classics that are romance (aka Austen).

I’m a big fan of underwater settings, especially when the world is shaped around it, and I’m a bit obsessed with the worldbuilding for ‘A Letter to the Luminous Deep’. Because we’re hearing the entire story through letters and field notes, it’s not until we start to get some excerpts from books shared between the correspondence that it starts to be revealed why most people live on strange floating cities or the one remaining land mass, but even by 50% of the way through the novel, my understanding of what exactly happened was shaky. It was a tad frustrating, but I just chose to suspend my disbelief and try and be a bit more patient. A slow drip of world-building is definitely better than an overwhelming info-dump!

Want to know what else made me happy when reading this book? E and Henerey.

They. Are. The. Sweetest.

I fell in love with their friendship and their burgeoning relationship really quickly, and everything that we learned about them fuelled the mystery of their disappearance and how unlikely it seemed with their personalities. I really didn’t expect the mystery element to be so compelling but it was equal footing with the romance for me which is really unusual. I think that was actually helped by the limited information we were given about the world at the start and I loved watching them unfold the mysteries surrounding them.

One of my favourite things about split narratives, whether dual POV or dual timeline, is watching them interweave and things fall into place on both sides. In this novel in particular, it really felt like the waiting paid off, and it ended up making a lot of sense outside of the necessity of the structure of the novel as we learn about what led up to E and Henerey’s disappearance, and the history of the Deep House and its creator.


I am so glad this book lived up to the gorgeous cover for me and the way that the plot developed has me incredibly excited for book two in ‘The Sunken Archives’ which the end of the book promises will be arriving in 2025!

Sylvie Cathrall’s debut is a magical light academia brimming with charm, romance and a vivid and mysterious world that’s begging to be returned to.

‘A Letter to the Luminous Deep’ by Sylvie Cathrall will be published by Orbit on 25 April 2024. Thank you to Orbit and NetGalley for the review copy.

Actual Rating: 4.5

A cosy fantasy, with an absolutely stunning cover, written mostly in the form of letters and set beneath the sea; how could anyone possibly resist that? I certainly couldn’t and I’m thrilled to say that my first dive into the cosy fantasy world (somehow ‘Emily Wilde’ is still on my TBR) was a resounding success. With charming characters, an intriguing setting and a delightful epistolary format ’A Letter To The Luminous Deep’ was a dream come true.

It didn’t take long for the characters within this novel to charm me. There’s something so sweet and heart warming about watching two socially awkward individuals fall in love via the written word. The romance really burrowed beneath my skin and found its way into my bones. There’s one section – involving the suggestion of a note on a window – that made me laugh and melt at the very same time. Henerey is such a warm, sweet individual that you can’t help but fall for and E is someone that I connected to in a way that I truly did not expect. As someone who struggles with severe social anxiety I felt a rare sense of acknowledgment seeing her struggles show up on the page. The OCD side of her storyline was wonderfully depicted too, capturing the sorts of intrusive thoughts and overwhelming compulsions that can consume an individual.

Possibly due to this personal connection it was E’s story that I fell into most swiftly but with time I came to adore my time spent reading letters exchanged between Sophy and Vyerin too, as well as discovering the story behind the Ridge Expedition. If anybody picks this book up with a particular interest in its deep sea setting then this dynamic will make it a must read for you. Truthfully I think I would have found myself engulfed by this side of the story sooner (as I was riveted by it once I got about a third of the way in) if I’d been more experienced with sci-fi novels as some of the terminology felt as if it was going straight over my head initially.

Besides feeling a little lost by those elements early on I adored exploring the setting and discovering a truly mesmerising world. The overall storyline went in a rather different direction than I’d initially anticipated too and by the end of it I simply could not put this book down. For the first book that I’ve read in the epistolary format in a very long time it was utterly delightful to find myself as riveted by the plot as I was charmed by its cast of characters.

Altogether I wholeheartedly recommend ’A Letter To The Luminous Deep’ and simply cannot wait to return to its world and characters with its sequel. It’s the perfect example of a cosy novel with a warm mixture of characters who can’t fail to charm you yet has a twisty plot that left me speechless by its end. Thanks to my rather unexpected affinity to E this book will also hold a special place in my heart for quite some time. Needless to say I’ll be sure to check out more by this author.

I'm enjoying this book so much I honestly can't wait to finish it to leave feedback. I'm over halfway and honestly obsessed with this writing style. Definitely reminiscent of the Emily Wilde books, but in it's own way. It's also taking me back to my days of playing bioshock! I'd love to see an illustrated version of this book given how descriptive and poetic some of the writing is. I could definitely see this as a Fairyloot/illuminate/owlcrate etc special edition.

I'm surprised by how easy it is to follow the story in the format of letters amongst a variety of different recipients. Initially I thought I might struggle to keep up, but the way it flows and all fits together is so seamless. This book has absolutely exceeded my expectations in all ways and I will definitely be buying a physical copy to add to my bookshelf.

Thank you NetGalley and the publisher for the opportunity to find treasures like this and review them for everyone else to fall in love with.

Epistolary novel set in a vaguely Victorian, steampunk-ish, watery world. Sophy and Vyerin form a bond through letters as they work through the archive of their missing siblings (Sophy's sister E. and Vyerin's brother Henerey)- who had formed their own bond through letter writing, until a catastrophic event destroys E. home and they both vanish.

Short review: Not for me, but others will probably love it

Long review: I thought I'd really like this, but it just didn't land at all and I was mostly bored reading this. I don't want to go on a long rant, so I'll try to break it down into what didn't work for me - but maybe it will for you.
- Pacing: Slow, in fact it reads like an extremely long prologue to the next book (surprise! It's a series). It was all overly wordy and I found myself skimming to reach the useful bits of information.
- Format: Entirely written as letters, messages, diaries etc. I think this was too much of a stretch for the story and would have benefitted from occasionally ditching the epistolary format. This would have helped with pacing and character development.
- Characters: As we only know the characters through the letters you need a unique voice for each one but the writing wasn't distinctive enough to tell the characters apart.
- World-building: the setting is basically background to the letter writing. Yes, there's an expedition to explore a mystery and other characters are also investigating a mystery thing but it didn't feel like a fully realised world.
- Resolution: there is none. Like I said, it's like a really long prologue.

I think many people will enjoy the epistolary format, the whimsy and the romance. Sadly, it just didn't work for me.

Thank you to NetGalley and the publisher for an e-ARC to review. All thoughts are my own.

Prefacing this review that I applied for this novel as an ARC because it was recommended for fans of Emily Wilde's Encyclopaedia of Faeries by Heather Fawcett, which happens to be my favourite fantasy series for the past year. There are not a lot of books like Emily Wilde, so I was anticipating reading A Letter to the Luminous Deep for the longest time because the synopsis sounded magical and had me rather curious. This was poor marketing by the publisher because aside from the fact that both books are not told in a more traditional storytelling format - Emily Wilde is solely by journal entries, and this is letters - there was nothing remotely comparable.

Sadly, this book didn't hit the mark for me at all. It's all letter correspondence in two different timelines, and whilst I did appreciate the further I got into the novel that dialogue or some sense of story-telling did begin, it didn't read comfortably. I found myself exasperated very early into reading with how all the letters from several different characters sounded as though they were written by the same person. All of them relied on writing in a similar format, ending their correspondence with a plethora of postscript. And I hope I never read read a book that heavily relies on bracketed content with an overuse of exclamation points like this again. It was incessant throughout this book, and it didn't matter what type of character it was that was writing, they all sounded way too enthused at every point of the way! Yes, I do come at this review with some sass but I found it extremely difficult to get a read of any individual personality traits and that made the correspondence feel like one big blur of a fever dream set underwater.

Perhaps I'm simply not the right reader for the humour and writing style expressed in this book. And that's okay. Unfortunately, I feel morally obligated to read books in full if I get them as an ARC, and this book subsequently suffers from getting a low rating because I couldn't DNF instead as I would if I had sourced it after publication.

I loved A Letter to The Luminous Deep and would highly recommend it. The unique writing style/structure is instantly interesting and draws you into the story making it hard to put down as you'll just want to read more of the letters to learn more about the characters and the mystery of the structure. I felt so immersed in the story that I didn't want it to end. I very much look forward to reading book 2! If you enjoyed Emily Wildes Map of the Otherlands by Heather Fawcett and Divine Rivals by Rebecca Ross you'll enjoy this too.

Although I loved the way that this book was written - all letters between characters - I was slightly let down by the world building. Although I expected things to be revealed slowly because of the format, I didn't expect to be quite so confused for quite so much of the book. Additionally, although the writing was beautiful and I loved the author's style, the characters didn't feel distinct. I would forget in a chapter who was writing!

I received a copy from the publisher in exchange for an honest review

Thank you Netgalley and the publisher for an e-ARC in exchage for my honest review

3.5 rounded to 4

This book was not at all what I expected. Yes, I was aware it would be an epistolary novel, but that was where my expectations ended. I would absolutely say that promoting this book as fantasy does it a complete disservice. This is a sci-fi novel through and through, from the otherworldly setting to the complexities of the society and technology.

That being said, I struggled for a good portion of the book to fully grasp said society and world. Our understanding of it is narrowed by the book's letter-based nature, although the characters do explain a great many things to each other at multiple points. I'd say I was lost until around 40% in, and that the main exciting plot points didn't start until about 70% in.

I would suggest not picking this up if you aren't a fan of a more old fashioned type of writing. The novel has been compared to the Emily Wilde books, and while I can see why - a focus on academia, strange happenings, a different format - it is very different in style and tone.

I had a hard time completely discerning between the different voices of the characters - it seemed they all shared a writing style and at times this bothered me. I'd hoped for more distinct voices, especially between the main protagonists E., Henerey, Sophy and Vy. It made me feel a bit detached from the characters and their story.

Having said that, once the mysteries started unravelling towards the 75% mark, the tide turned (pun intended) and I started to feel more engaged. Yes, it's a bit of a slog to get there. Yes, the prose can be VERY dry and at times characters go off on strange tangents for a little too long. BUT there was something strangely charming about this submerged science-fiction world full of Victorian sensibilities and academic pursuits.

Will I pick up book two? Yes I probably will. I am very intrigued by the ending and want to know what happened to E. and Henerey.