This movie focuses on the last half of Osamu Tezuka's revered saga of a white lion's quest to become king of the jungle. Leo's newborn cub, Lune, takes an interest to humans after discovering a music box in the wreckage of an airplane. At the same time, a greedy treasure hunter known as Ham Egg is leading an expedition team of rough-looking men on a trek for the fabled Moonlight Stones, which can supposedly save the world from an energy crisis. Two other humans, (who go by the rather wacky names of Dr. Moustache and Lemonade) try to stop Ham Egg's mad destruction of the jungle. Later, a terrible virus sweeps through the jungle, poisoning many of the animals. Dr. Moustache comes to save them with a cure. The film culminates with a treacherous journey up the legendary Mt. Moon in search of the stones....

(Source: Anime News Network)