When Echo injures her tail, she can|t compete in the Poseidon Tail Flippers team competition. Will Echo find a way to help her team win from the sidelines?

"Shelly Siren and her friends visit King Neptune's royal castle and attend their first ball in this Mermaid Tales adventure"-- "Shelly, Echo, Kiki, and Pearl are spending their school vacation at Neptune's castle! Shelly's aunt, Queen Edwina, has invited the girls to stay for a whole week, and while they're there the girls can't wait to visit the Royal Orca Museum, see the Palace Library, ride seahorses, and maybe even attend a royal ball. Shelly...

Shelly Siren loves playing on Trident Academy's Shell Wars team. But is she ready to compete in the Shell Wars Championships in the fintastically famous city of Atlantis? As part of their trip, the mergirls get a tour of Atlantis and swim through Poseidon's Temple where Shelly sees a spookfish, which according to legend, carries a horrible curse.

Echo's third grade class visit the Titanic and figure out a way of including their new classmate, Anita, who is confined to a wheeled chair.