A review by niffler_for_words
A Letter to the Luminous Deep by Sylvie Cathrall

adventurous challenging emotional informative inspiring mysterious reflective tense medium-paced

• Plot- or character-driven? A mix
• Strong character development? It's complicated
• Loveable characters? Yes
• Diverse cast of characters? Yes
• Flaws of characters a main focus? It's complicated

5.0

“Reading your letter was an experience like no other. Have you ever considered, E., that someone ought to write a Fantasy about you?”

A letter to the luminous deep was a UFO (Unidentified Floating Object) to me, and I mean that in the best of ways. Everything in it surprised, unsettled, passionated me. If you asked me to put this story in a box, I’d have a lot of difficulties. You’ll find a fantasy underwater world full of bioluminescence, a lot of scholars, some romance, a mystery, etc… I wouldn’t say one part takes the lead on the other, making the story very balanced.

The whole book is constructed around correspondence. We follow several epistolary relationships, in –mostly– two points in time. Besides the letters exchanged, we can also read bits and pieces of journals, newspaper’s articles, books’ abstracts, etc. That’s for the form, and I truly enjoyed that. 

The back and forth with time isn’t a problem at all, as we discover E. and Henery’s story (and the circumstances behind their mysterious disappearance) more or less at the same time as their siblings. The other letters and “documents” are a very clever way to make the story progress seamlessly. It was also a great opportunity for character building. The characters are very lovable (E. !!!), and express diversity (neurodivergence –even if no true label is put– and LGBT+ especially). 

The form also allows the author to build the fantasy world with a lot of subtlety. I found the reading very immersive, and experienced a lot of synesthesia in the manner the places and actions were described. 

I would say the first ⅔ are slow paced, which for me was very enjoyable as it’s how I like fantasy books. The last third, though, as the mystery begins to really unfold, is a torrent of information and quite a page turner. I was surprised by the “political” turn of events, about how the scholar system and the environmental problems (and so on) are handled here, and I can’t wait to learn more about this whole world in the second book. (I didn’t know this was a series until the end of the book, but the end remains a satisfying one in itself.)

Thank you NetGalley, Sylvie Cathrall and Orbit book for that wonderful ARC!