Antonia is thrilled to win first prize in the Sea Watch poster competition – a dolphin charm necklace. But when she is presented with it, she is mysteriously told to ‘always answer the call’. Soon she discovers that her necklace has magical powers that draw her to the sea where she meets a pod of dolphins and learns she has been chosen for a very special role. But Antonia’s new responsibilities not only conflict with her friendships; they also bring her into danger. Is she brave enough to face her fears? And can she be a Silver Dolphin without losing her best friend?