O’Shea creates a fantastical yet harrowing story inspired by Hans Christian Anderson’s mermaid tale but set in 2242 after a global catastrophe. Daniel Manston, medic and occasional bodyguard to the crown prince of the nation of Anglia, fails at his duty: On an incognito excursion to Denmark, the prince is viciously attacked by a mysterious woman who vanishes into the ocean. After tense interrogation, Daniel is given two options for how to pay for not protecting his charge: accept a death sentence or fake his death and take a clandestine job as a spy. Choosing life, Daniel’s assignment leads him on a quest to track down a century-old scroll known as the Angel File—and secrets about the past, the relationship between humanity and the sea, and even about Daniel’s own identity.

While the first half of Daniel’s adventure features rapid action, mayhem, and murder, the second half settles into a delicate volley between his present predicaments and the world that existed before that global catastrophe that upended everything (and connects The Other Mermaid to O’Shea’s science fiction/steampunk series, Kingdom of Clockwork.) Daniel teams up with a woman hermit, Deryn, who serves as a research partner, friend, and love interest. Together, they seek answers to questions never meant to be asked, and O’Shea explores the past through a fascinating series of transcriptions from scientists outlining trailblazing research regarding communication between humans and sea creatures.

With a mix of sci-fi and fantasy as well as a splash of romance, O’Shea’s genre-bending mystery captivates with compelling characters, polished prose, and subtle yet ever-present tension. The intrigue into the Angel File mystery keeps a firm grasp on the reader’s attention. Daniel is a well-developed protagonist whose relationship with Deryn allows both characters to express a vulnerability relatable to readers. With themes of love, family, and redemption, O’Shea’s story is a satisfying read for those looking to escape into a future world where myth and folklore become reality.

Takeaway: An accomplished genre-crossed adventure with compelling protagonists set in a future of mythology and mystery.

Great for fans of: Mira Grant’s Into The Drowning Deep, Alexandra Christo’s To Kill A Kingdom.

Production grades
Cover: A-
Design and typography: B
Illustrations: N/A
Editing: A
Marketing copy: A-