Growing up in an orphanage in the British countryside, Earwig has no idea that her mother had magical powers. Her life changes dramatically when a strange couple takes her in, and she is forced to live with a selfish witch. As the headstrong young girl sets out to uncover the secrets of her new guardians, she discovers a world of spells and potions, and a mysterious song that may be the key to finding the family she has always wanted.

Featuring the voices of Richard E. Grant, Kacey Musgraves and Dan Stevens, "Earwig and the Witch" additionally features an English language theme song performance by six-time Grammy Award-winner Kacey Musgraves. Based on the children's novel by Diana Wynne Jones (Howl's Moving Castle), the film marks Studio Ghibli's first 3DCG animated feature.