Saoirse is an enchanting little girl who lives with her grandmother in Ireland. There is much more to this child than meets the eye, however. It turns out that she is a selkie. These mysterious beings live as seals in the ocean, but they take on human form outside the sea. She decides that the time has come to return to the sea, and she leaves her home to undertake a perilous journey. On the way there, she meets many others who may have a hidden identity about which they have no knowledge, and she awakens them to their destiny.