Marina, Aqua and Oceana are brave pirates, always ready to help. They live on the wonderful ship “Ryushechka”, which they manage themselves. The girls bravely swim the seas, dive to unimaginable depths and even dive underwater on a magical submersible. They also know a lot about fashion. Satin dresses, decorations made of shells and, of course, extremely stylish blindfolds, like real pirates! In the Littorina Lagoon, where the girlfriends live, a grandiose seahorse riding competition is being held, to which, unexpectedly for everyone, Queen Medusa’s subjects arrived . To win, they used forbidden magic and even sent hordes of jellyfish into the lagoon. The pirates have to go on a dangerous journey and save their home from witchcraft...