Nicholas, a hypocritical ruler of the Zinba Empire, wants to expand his territory. His plan is to turn the Earth into his own private colony. His detailed plan starts by cutting off all of Earth's defense forces by destroying the city of Orion. Meanwhile, a group of youngsters are spending their vacation on Mars. Not until they discover the destruction on Earth do they realize the danger they are in. They find Dr. Han and Fred in an underground cave. Dr. Han believes that somewhere on Earth there is an immortal bird called the Phoenix King. He is said to be the guardian of the Earth and only this mythical creature can defeat Nicholas. Therefore, the adventurers set off for the Phoenix's alleged home and the Earth's only hope.