Long ago on Earth, a kind and just King Dinosaur ruled. But a sly and treacherous courtier, with flattery and deceit, managed to win the king's trust and seize all power. Meanwhile, deep in the forest beyond Marble Mountain, Abu—the son of King Dinosaur—is born. Under the care of an old and wise lemur, Abu grows stronger and learns skills. Now, taking his friends, a crow, a monkey, and a squirrel, as allies, Abu is ready to free his father and save all the forest animals.