Title: A Letter to the Luminous Deep
Author: Sylvie Cathrall
Publisher: Orbit
Publication date: April 25, 2024
Length: 432 pages
Genre: Fantasy
Source: Purchased
Rating:

In the world of A Letter to the Luminous Deep, human life is lived on ships and floating anchorages, on a planet with only one small land mass. Legend has it that one thousand years earlier, a cataclysmic event known as the Dive occurred: Before the Dive, people lived in the sky (on spaceships? orbiting stations?), but the entire civilization suddenly plummeted into the seas below. Relics of the pre-Dive world are still occasionally found, but humanity now lives on the water’s surface — or occasionally, below it.

As the book opens, we’re introduced to E. Cidnosin, a young woman who resides alone in Deep House, the underwater compound built by her late mother. E. prefers the solitude, as it keeps her brain calm and allows her a peaceful life. When she spots an unusual sea creature outside her window, she writes to a renowned scholar, Henerey Clel, to ask for help in identifying it. From that initial contact, the two develop an ongoing correspondence, through which they reveal more and more of themselves and grow to truly connect and care for one another.

Sadly, what we learn early on is that E. and Henerey were presumed dead after an explosion at Deep House. Now, a year later, E.’s sister and Henerey’s brother are trying to piece together what happened by sharing their siblings’ notes, letters, and journals. As they correspond, they form a friendship of their own, and become deeply involved in solving the mystery of E. and Henerey’s fate — and trying to determine if another mystery with worldwide implications might be at play.

I wanted to love A Letter to the Luminous Deep, but realized almost immediately that it wouldn’t work out that way. Epistolary novels are tricky: There are plenty I’ve enjoyed, but they only work if the letters are informative enough to give readers a bigger view of the letter writers’ worlds. That was not the case here. Perhaps the author’s intention was to keep an air of mystery throughout the book, but for me, the result was a lack of information that kept me from engaging with the story.

We get a sense of the world through the letters, but details are dripped out so sparingly that I felt frustrated rather than intrigued. Meanwhile, the characters themselves are hard to connect to. I couldn’t imagine much about E. or Henerey beyond their words on the page, and the lack of definition of elements of their world makes it hard to get a fuller picture of their daily lives and experiences.

With the epistolary format, all content is provided through letters and documents, and the writing style of the characters is highly stylized. Without any other narrative to provide more straightforward language or descriptions, that writing style gets tiresome very quickly.

I will say that the story picks up in the final third, and by the end, there’s a payoff for sticking with it. Still, too much of the book feels like a slog, and at over 400 pages, that makes for a less than satisfying read.

A Letter to the Luminous Deep is apparently the first book in a duology, with book #2, A Letter from the Lonesome Shore, due out in spring 2025. As of now, I can’t seem myself continuing with the story.