When Evan O'Neil inherits his grandparents' tiny, private island off the coast of the sleepy seaside town of Palmetto Dunes, he and his wife relocate there to begin life anew. But, upon arriving, they find a town and a people strangely untouched by time.

It seems that Palmetto Dunes harbors a dark and deadly secret, and that the sea around their tiny island home might well be the beating heart of that evil. For something monstrous calls the surrounding ocean home, something with a deadly reach that extends well beyond the endless tides.