Ten years ago, Doctor Shizuma invented an environment friendly energy system that was to save the planet from ecological ruin, but now he finds himself being pursued by a mysterious organisation who want the attache case he is carrying with him. They are about to catch him when Giant Robo and the Experts of Justice intervene to stop the case falling into the hands of the villainous Magnificent Ten.

Peking is under attack from the fearsome Lord Alberto. Kenji Murasame prepares his ultimate weapon and the Experts of Justice are trapped behind the Big Fire's force field, powerless to intervene in what could amount to a new dark age.

Three nights have passed since the terrible device known as Von Folgers' Eye was unleashed on Paris, and now its unstoppable course has taken it across Europe and America. The Experts of Justice launch the mighty airship Greta Garbo, but the forces of Big Fire are not content to stand by and watch their masterpiece defeated.

Giant Robo lies in ruins after the magnetic attack on Von Folger's Eye failed. Taiso, meanwhile, confronts his old enemy in an attempt to buy his colleagues more time to escape the doomed city before the Eye activates.

Genya returns to Big Fire's secret headquarters with a new plan to put a cessation to the hostilities once and for all. As the surviving Experts of Justice regroup and nurse their injuries, they learn that neither Giant Robo or Agent Gineri are now trusted by Interpol. The Expert's resources are now truly stretched to breaking point, especially after the final attack on Saint Abbe.

Emmanuelle acquires the third sample, prompting both Chief Chujo and agent Ginrei to prepare for the ultimate sacrifice.