In this sequel to The Princess and the Goblin, Curdie has returned to his life as a miner and has dismissed the supernatural happenings of the past, believing them to have been a dream. When Curdie callously wounds a pigeon, his conscience leads him to Princess Irene's mystical great-great-grandmother for help. She has him plunge his hands into a pile of rose petals that burns like fire. Extraordinarily, this grants him the power to see what kind of "animal" a person is at heart.

She then sends him on a quest, accompanied by a peculiar doglike creature named Lina, who was once a human. However, Curdie must resolve his own skepticism before he can use the powers granted him to defeat the evil that is threatening the future of the kingdom.