Before disappearing at sea, Marissa Pruitt's father-a once revered marine archaeologist-walked the line of insanity, claiming to have seen a mermaid during an ordinary dive in the Gulf of Mexico. He abandoned his life and career, completely obsessed with chasing the truth. It's been years since his death, and Marissa is still tormented by countless unanswered questions. When she finds dive coordinates and a stone pendant hidden in her father's things, she asks for help from his old protégé and sets out to give her father one last goodbye and maybe find closure for her troubled heart. Instead, she finds the truth he'd been searching for all along, with a life and love she never could have imagined. But there's a price to see it all, one set by betrayal and paid with an anchor at her feet and salt water in her lungs.