Just as Scarlett and her friends start to make their way back to Coral Kingdom with the magic crystals for Queen Neptuna, a storm whipped up by the evil Mantora, throws them right off course! Scarlett and her fellow Sisters of the Sea are lost, but they must find their way home as quickly as possible in order to complete their important mission. Scarlett comes up with a plan to help her mermaid friends, as well as saving a family of seals's beach from a very messy end.