David Wiesner's first graphic novel, created in collaboration with esteemed author Donna Jo Napoli, is set in a boardwalk aquarium--a house filled with water--run by Neptune, god of the seas. At least that's how the Fish Girl, a mermaid in the aquarium, knows him. As the main attraction, she is tasked with showing visitors only glimpses of herself without fully revealing her mermaid identity. An octopus in the tank is her only friend and protector. By accident a visitor, an ordinary girl, sees her. Unbeknownst to Neptune, they become friends, even though Fish Girl can't speak. Her new friend, Livia, gives her a name, Mira, and tells her fascinating things about the world. At the same time, Mira is becoming suspicious of Neptune and hauls herself out of the tank to see if he is truly god of the seas, but he's a sham. She discovers that he has lied to her all along: he's no god, only a fisherman who happened to catch her and Octopus in his net. He's just using her to make money. Repeated journeys outside the tank reveal that Mira now has legs on land. She gains strength enough to venture out of the aquarium into the outside world, free of Neptune's clutches. At the crisis when she shows Neptune who she has become, a violent storm--perhaps summoned by Octopus--attacks the building, the tanks are destroyed, and all the creatures in the aquarium are released back to the sea. Mira escapes, and finding her voice, she calls to Livia, who welcomes her as a sister.