Jo, a witty 9-year old terminally ill girl is taken back to her rural village to live out the rest of her short life. Her only comfort during these dull times are her dreams of being a superhero, which prove to be something her rebellious teenage sister Mwix, overprotective mother Kathryn and the entire village of Maweni think they can fulfill.

A poor but ambitious fisherman enslaves a mermaid-like water spirit and exploits her and her abilities for wealth and power.