Sylvie Cathrall's debut is an epistolary novel - a novelistic style that sometimes works for me and sometimes does not. Here it mostly does. I was immediately drawn in by the dreamy, carefully anxious letter that E. is writing to Scholar Henerey Clel. E. (you'll learn her full name later) lives alone in an underwater abode called The Deep House. She writes to Henerey and her sister Sophy and an array of others to stay in contact with the world. This world is one that is about 99% covered in water and most abodes are on floating islands. For Henerey getting a letter from a resident of the famed Deep House is of immediate interest, but once he begins to read E.'s words, he's immediately drawn to her herself. E. and Henerey's letters are interespersed in the present day (of this world) by letters between Sophy and Henerey's brother Vyerin who have come to know one another, via correspondence, after some accident has befallen their sibilings. As they follow the timeline of their sibling's relationship, we, the readers learn more about them all and what has got them to this point.
This is a blending of fantasy, romance, and mystery and that's a good thing to this reader's view. But fair warning, it's a slow build. And that's where the "mostly" of how it works comes in. In the first chapters I was charmed and entranced by the writing, the world-building and the introduction to the cast of characters. Cathrall had me. But somewhere in the middle I did have moments where I wondered 'when is something going to happen?'. The author does get there and the pace really picks up in the last third so that I do recommend it overall, especially if you're someone who reads for character and atmosphere (of which this book has loads). If that's you? Sink into the deep and enjoy.