As her seventeenth birthday approaches, half-mermaid Tempest Maguire will have to make a decision. Stay on land? Or give herself to the ocean? The pull of the water becomes as insistent as her attraction to Kona, a gorgeous surfer whose uncanny abilities hint at an otherworldly identity as well. And when Tempest does finally give in to the water's temptation, she finds that a larger destiny awaits her-and that the entire ocean's future hangs in the balance.