A diver is alone in shark-infested waters after her twin sister abandons her in this romantic suspense mystery by a New York Times–bestselling author.

Briana Devon knows her twin sister would never deliberately leave her—but when she emerges from underwater, Daria and their boat have vanished. Fighting rough waves and a fast-approaching storm, Bree doesn't have time to question: if she wants to survive, she has to swim. Exhausted and terrified, Bree barely makes it to a tiny barrier island, where Cole De Roca, who has also taken shelter, revives her. Bound to Cole by the harrowing experience, she turns to him as she struggles to understand what happened to her sister. What was her twin, whom she thought she knew so well, hiding? What really transpired that terrible afternoon? And what secrets lie dormant . . . below the surface?

"Below the Surface is a well plotted mystery that had me guessing until its exciting conclusion. . . . A nice mystery to curl up with on the beach this summer." —Fresh Fiction