The mermaid queen is dying, and Kiera's in line for the crown.When Kiera left her life in Marmor, the underground mermaid queendom located in the Bermuda Triangle, she forwent her tail and traded it for legs. Now, engaged to the man of her dreams, the sea calls with news that threatens to turn the tide.Kiera doesn't want to give up the life she's created for herself, but her mother's illness draws her back to the sea of grief and to the world she left behind.She's forced to decide which is stronger: her inheritance in the sea or her new life on land.