The evil Mantora has stolen six precious Snow Diamonds from Ice Kingdom. If they are not found quickly, and returned to their rightful place, then Ice Kingdom will melt, causing devastation to many creatures' habitats - including that of the Merfolk's.
However, with each hidden Snow Diamond, Mantora has left a clue to where the next one can be found. It is up to six young mermaids to solve all the riddles in time for Ice Kingdom to be saved.
Amber leads her friends to the first Snow Diamond and the next clue. When they help a young Inuit girl to save her friend, a beluga whale, the mermaids are introduced to a humpback whale who will carry them swiftly to their next destination aboard the Whale Express.