Dive into another exciting magical adventure for girls - will you answer the call of Silver Dolphins? Antonia is a secret Silver Dolphin - she's responsible for helping the creatures of the bay when their environment is threatened, by responding to the call of her magic necklace. Antonia and Cai are helping Hannah set up another Sea Watch charity to look after local dolphins and seals. But when thunderstorms cause a landslide, the Silver Dolphins face their biggest challenge yet...