In Sand Land, a desert land, Sheriff Rao decides to go in search of the legendary spring to save his village where people are dying of thirst. Beelzebub, prince of demons, and Thief, expert in flight, soon join him.
The trio replenish their supplies in a nearby village when they come across a king's army tank. After taking the vehicle, the king's army plane discovers the theft and engages in battle.
Rao's tragic past is revealed, but he continues to fight Zeu and the royal army; General Are seeks revenge and leads his tanks into battle against the trio who steals a tank from the royal army.
After Rao reveals the truth about the tragic explosion to General Are, the Swimmers suddenly attack. But, when Beelzebub sets off to capture the Swimmers, alone, he makes an incredible discovery.
The trio vow to keep their discovery a secret. They take their tank to the royal army's water supply, where they learn the truth about the royal spring and must confront Supreme Commander Zeu and his insect men.
A furious Beelzebub overwhelms the bug men with his diabolical powers; when Rao and the thief infiltrate the king's army's mega-aircraft carrier to stop Zeu, Rao clashes with him, but Zeu is hard to defeat.
Mutsumi Tamura
Beelzebub
Kazuhiro Yamaji
Rao
Yūichi Nagashima
Thief
Satoshi Tsuruoka
General Are
Nobuo Tobita
General Zeu