Ariel's never seen anything outside of her boring life. So when beautiful, mysterious, heartbreaking Callin Day needs her help to break a century-old curse, she's unsure what to do. Should she follow him into a world of magic and mermaids, hidden away under the sea? Or should she remain with her feet planted firmly on the ground? But when she finds herself wrapped up in the curse as well -- and falling for Callin himself, does she even have a choice anymore?