In the midst of the worst heat wave Grand Cayman has seen in years, an early morning explosion rips through RIO, the oceanographic institute run by underwater photographer Fin Fleming, leaving a young mermaid performer badly injured. What appears at first to be a shocking act of sabotage soon proves to be only the beginning of a nightmare.
Fin is no stranger to danger. But her husband has disappeared from the set of his latest movie, and her brother's been missing ever since he worked an undercover sting operation. And with most of her usual team away at an international dive conference, Fin is left to face the crisis largely on her own as the attacks continue to spread.
Fires and explosions strike at sites across the island, and every target is linked to Fin and the people closest to her. Now, with the help of new friend Charity Styles, Fin must draw on every skill she has to stop the destruction and find the people she loves.
Because in the sweltering waters off Grand Cayman, the next strike could come from anywhere-and this time, survival is only the beginning.
To save the people she loves, Fin must rely on the instincts that have carried her through dangerous dives: stay calm under pressure, trust what others overlook, and keep moving even when the way ahead is dark.