Sunlit Haven, marine biologist and animal rescuer extraordinaire, is happily scrubbing down her Marine Sanctuary when destiny strikes. Word of her efforts in Seaside has spread down the coast, and now the director of a zoo run entirely by talking animals wants her to take over the care of two very colorful porpoises.

When an animal's wellbeing is at stake, Sunlit is only too happy to pitch in. But she's never ventured so far from Seaside before, and she soon runs into trouble. Not only is there the question of how to transport the porpoises and how to treat their magical affliction, there's the difficulty of dealing with the zoo staff . . .

But Sunlit has even bigger problems. Back in Seaside, the porpoises attract attention–too much attention. Some people are curious and supportive, but others begin to protest Marine Sanctuary's presence on the beach, saying that animal care has no place on the boardwalk. Anxious even at the best of times, Sunlit is overwhelmed as she tries to navigate this newfound notoriety.

Fortunately, she has her friends to help guide her. From Joy, the giant otter, to Fish, Chip, and Ige, Sunlit's unofficial adoptive family, the one certainty is that Marine Sanctuary won't be standing alone. Sunlit will need all the help she can get to heal the porpoises and figure out which of her new acquaintances is truly "beastly."

And along the way, she just might learn that sometimes speaking up isn't quite as dangerous as it seems.