Grace has been fascinated by a pack of wolves in the woods near her home for years. She is particularly drawn to a yellow-eyed wolf, whom she believes is her own. Meanwhile, Sam is a boy who lives as a wolf in the winter and a human in the summer. When Grace meets a yellow-eyed boy who seems familiar, she realizes it must be her wolf. However, as winter approaches, Sam must struggle to maintain his human form or risk losing himself and Grace forever.