Ophelia and Lana are twin sisters who live with their aunt and uncle in Dublin. While exploring the basement in their seaside cottage, they find something that makes them question the fact that their parents are away on business in America. Suddenly, they are plunged head first into the adventure of a lifetime in the underwater kingdom of Jade Bay, hoping to discover the truth about their family's past. The fate of Jade Bay and the Siren People are in their hands. Will they be able to do it all?

"Why jump?" "Do you know what another word for 'autumn' is?" she asked. He stayed silent. "Fall."

A collection of notes, a public library, two teenagers, and zero spoken communication.