Refusing to embrace her mermaid heritage, Gwen Lonike prefers to live as a human. All she wants it to run her hotel in Port Rock Maine, in peace. But when her sister Tessa returns from the Mediterranean with news that she had inadvertently opened the gateway to a lost mermaid kingdom–and accidentally freed its dangerous queen–Gwen can no longer hide behind her idyllic life.

Covert-ops agent Blake Whittaker is far from happy when he’s assigned to trail paranormal activity back to him hometown, where he can’t escape crushing memories he’d rather forget. But when he meets and falls for Gwen, he knows he can’t cut and run. Yet how long can he hide his true mission from her? And how long can Gwen and her sisters remain safe from a nemesis bent on their destruction–and from Blake’s own superiors, whose ultimate mission could prove the greatest threat of all?