Deep inside the mountain, goblins are plotting to destroy the surface-dwelling humans. They carry a long grudge against the king's family, and against the miners who serve the king. A poor young miner boy is the only one who suspects that anything is amiss, but no one believes him. Seeking proof, he sneaks into the underground goblin labyrinth night after night, carefully trailing the goblin sappers while trying to remain unnoticed.
Meanwhile, above ground, the carefully sheltered eight year old Princess Irene is blissfully ignorant of the danger below her-until her mysterious great-great-grandmother sends her, without the knowledge of her attendants, to rescue the poor miner boy.
This is George MacDonald's classic tale of the faith and courage of a poor miner boy and a young princess, retold for the enjoyment of modern readers.