Barbie stars as Merliah, a surfing champion from Malibu. But strange things begin to happen to her her hair turns pink, she can breathe underwater and can even talk to dolphins.Merliah soon discovers a shocking family secret; she’s a mermaid. Her mother is Calissa, the Queen of Oceana, but Calissa’s evil sister Eris has stolen the throne. Along with her dolphin friend Zuma, Merliah sets off on an undersea adventure to rescue her mother and discover her true destiny. She must get three items to succeed: the hair comb, a dreamfish and Eris’ protective necklace.