Penguin Island is known for being home to a rare population of fairy penguins, separated from the mainland by a narrow strip of land. Trouble is, that strip of land becomes exposed during low tide, and a local pack of foxes has discovered it!

When twelve-year-old Addie Jenkins realizes how vulnerable the penguins are, she decides to take action with Max, her faithful and protective sheepdog, by her side. Max becomes the colony's protector, keeping the foxes at bay and teaching the penguins how to defend themselves. But Darwin, a young and rambunctious penguin, doesn't trust Max, and the two can't seem to agree over what's best for the colony.

That's when a bad thunderstorm strikes, leaving the penguins suddenly alone and without protection. Will Max and Darwin be able to set aside their differences and work together to save the colony?