In a land far away, the sun and moon shine only thanks to heroic Guardians. But when an unlikely little creature, Mune, is chosen to be the new Guardian of the Moon, a vengeful ex-guardian takes advantage of his inexperience and steals the sun! Now Mune must team up with Sohone, the swaggering Guardian of the Sun, and Glim, a headstrong girl with a taste for adventure, to rescue the sun and save their world.