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Two bereaved strangers work to unravel the mystery of their siblings' disappearance in Sylvie Cathrall's dreamy, witty epistolary underwater fantasy, A Letter to the Luminous Deep, the first book in a planned duology.
E. Cidnosin is fascinated with the previously undiscovered "Elongated Fish" she spots through the window of the Deep House, her underwater home, so she writes to Henerey Clel, a natural history scholar and complete stranger. Her social anxiety leads her to exhort him not to read her letter but to "crumple it into an abstract shape that might look quite at home on a coral reef." He does not, and the pair fall in love over a series of letters. One year later, E.'s sister, Sophy, writes to Henerey's brother, Vyerin, to ask for help unraveling E. and Henerey's tragic disappearance in an explosion that destroyed the Deep House. Sophy and Vyerin swap the papers their siblings left behind and uncover a mystery involving a lost society, unexplained underwater melodies, and a glass object dubbed "the Structure" that inexplicably appeared in the Deep House's garden.
Cathrall's characters speak with a whimsical Victorian-esque wryness that allows for sly one-liners, effusive descriptions of sea creatures, and deep, understated passion. Her world-building combines an island-dwelling culture, whispers of ancient technology, and deep-sea exploration in the name of academia to create a soft and satisfying blend of science fiction and fantasy, perfect for fans of T.J. Klune's In the Lives of Puppets. This love letter to sibling bonds and uncharted depths will beguile readers. --Jaclyn Fulwood, blogger at Infinite Reads