The coastal town of Bristol Cove is known for its legend of once being home to mermaids. When the arrival of a mysterious girl proves this folklore all too true, the battle between man and sea takes a very vicious turn as these predatory beings return to reclaim their right to the ocean.

Barbie is Kara - a modern-day princess with a normal life. Kissed by a butterfly which gives her superpowers and allows her to become a Super Sparkle, she is ready to save the kingdom from evil - were it not for her jealous cousin who is also kissed by the butterfly and becomes her rival and nemesis. Watch as Super Sparkle and Dark Sparkle learn that together they can become a great team for good once they learn the power of friendship.