Suspicion of Madness — Barbara Parker

For Gail Connor and Anthony Quintana, escaping their busy law practices and hectic lives to vacation in a private villa in the secluded Florida Keys seems too good to be true. And sure enough, their pleasure is soon interrupted by business--when a dangerously unbalanced former client becomes a suspect in a local murder. But the explosive undercurrents of the case go far beyond anything Connor and Quintana have encountered before. Now, as a tropical storm threatens to unleash its fury, they find themselves trapped among the strange and secretive islanders, and plunged into an escalating nightmare of unknown terrors, unexpected twists, and deepening madness...