"Thirteen-year-old Arthur Curry has enough troubles to sink a ship. His mom left him and his dad when Arthur was only three years old. He doesn't fit in with the other students at school. To them, he's just "fish boy," a weird, freaky kid. But Arthur has a secret. Something so secret, even he doesn't know what it is. Yet ... With the help of his only friend, Claudia, Arthur will begin to learn the truth about his mother, himself, and a legendary world...

When Paulina, one of the Thea Sisters, finds a strange blue-skinned boy unconscious on the beach, the sisters set out to solve the mystery of who the boy is and where he comes from--and how to return him to his home.