Merliah, the young queen of the quick Malibu waves, thinks that she is an ordinary teenager; however, after an unexpected incident during the surfing tournament, she discovers her true identity: she's a graceful mermaid. Now, with her new best friends--the happy bubblegum-pink dolphin, Zuma, and the beautiful mermaids, Kayla and Xylie--they embark on a fascinating underwater adventure to save the ocean kingdom of Oceana, and Merliah's mother, Calissa. The girls need to find three magical items. Will Merliah, the princess of Oceana, accept the great responsibility?