In a magical forest grove named Pixie Hollow, Fawn (Ginnifer Goodwin) is chastised by Nyx (Rosario Dawson) and Queen Clarion (Anjelica Huston) for looking after animals, such as a wounded hawk, that could pose a potential threat to fairies.

Fawn discovers a striped giant creature with fangs who is roaring in pain from a thorn in his paw. Fawn gently removes the thorn and names the fluffy beast Gruff. When Nyx discovers an ancient prophecy that says Gruff is destined to destroy Pixie Hollow, Fawn is determined to protect him.