Reading order
| # | Title | Published | Author | Buy on Amazon |
|---|---|---|---|---|
| 1 | The Girl Beneath the Sea | 2020 | Andrew Mayne | Buy |
| 2 | Black Coral | 2021 | Andrew Mayne | Buy |
| 3 | Sea Storm | 2022 | Andrew Mayne | Buy |
| 4 | Sea Castle | 2023 | Andrew Mayne | Buy |
| 5 | Dark Dive | 2024 | Andrew Mayne | Buy |
| 6 | Mastermind | 2021 | Andrew Mayne | Buy |
| 7 | The Final Equinox | 2022 | Andrew Mayne | Buy |
The Underwater Investigation Unit series takes crime fiction beneath the ocean. Starting with The Girl Beneath the Sea (2020), the books follow a Florida-based team that investigates cases with connections to the water. The underwater settings create natural tension, since every dive carries physical danger alongside the criminal investigation.
The series has grown to seven books, with Black Coral (2021), Sea Storm (2022), Sea Castle (2023), and Dark Dive (2024) among the entries. Some books also connect to the Theo Cray storyline. Mayne uses the Florida marine environment as more than just scenery, making the ocean itself a factor in the plots.