Poor girl Lily ventures into a treasure-filled dark forest to save her three-year-old sister suffering from leukemia, and stumbles upon an ancient castle that is actually a realm of the dead. Everyone inside the castle perished long ago, yet trapped there, they relive their old lives day after day, unable to leave.
Lily passes eerie interviews and becomes wheelchair-bound Prince Adrian’s midnight companion. Each night inside a golden coffin, her gentle presence gradually heals the prince and all lingering spirits in the castle. She discovers a painting of him as a dragon-slaying hero, but the truth is heartbreaking: to please his greedy mother, the prince plundered the people’s wealth, bringing disaster and the castle’s downfall. Persuaded by Lily, he returns all the gold to the poor, and the ghosts are purified and ascend. Though he was meant to vanish, he is revived from the painting by Lily’s kiss of true love, and embraces a new life with her.