A long time ago, there was a beautiful land made up of three nations: Fuji, Izumo, and Hyuga. This land was called Mizuho. The people of Mizuho disliked conflict, honored their ancestral spirits, and lived in harmony with nature. However, over time, they began cultivating crops, forging and using metal, fighting wars, destroying nature, and neglecting to honor their ancestral spirits.

In the meantime, various locations in Mizuho suffered from natural disasters like flooding, earthquakes, and volcanic eruptions. In order to stop a destructive eruption, the Queen of Mizuho, Tsukuyomi, sacrificed her beloved daughter Sakuya to the mountain, confined her other daughter Kaguya within a bamboo seal in case of future disasters, and then disappeared. 13 years later, Princess Kaguya has grown into a beautiful woman and her childhood friend, Kintaro, saves her during a riot. She rises against her "fate to be a sacrifice," and in order to follow her own path, they both escape from Fuji and journey across Mizuho to discover the truth behind Tsukuyomi's decision.