Years after defeating the Black Ghost organization, the nine cyborg warriors—Joe Shimamura, Françoise Arnoul, Ivan Whisky, Jet Link, Albert Heinrich, Geronimo Jr., Chang Chang Hu, Great Britain, and Pyunma—have retired from active duty. With the establishment of the United Nations Guardian troops, they have been relieved of their mission to protect humanity and now live quiet, secluded lives on a farm in Texas. Their creator, Dr. Isaac Gilmore, remains with them.

Their peace is broken by Lucy Davenport, a journalist who has learned of the existence of the Blessed, a cryptic group of superhuman beings who have secretly manipulated human history since ancient times. Few people believe the Blessed are real, but Lucy has evidence: a mysterious cube left to her by her father, which she believes holds the key to uncovering them. She travels to Texas to find the cyborgs and show them the cube. When they open it, the Blessed detect the activation and immediately attack. A member known as Cowboy launches a brutal assault on the farm, forcing the cyborgs to don their combat gear and fight once again. Soon after, another Blessed member, Teacher, also moves against them.

The Blessed are beings of immense power and intellect who have covertly shaped the course of civilization for millennia. Their ultimate goals are unknown, but they cast a dark shadow over the world. As the cyborgs confront these enemies, they also come under suspicion from the UN Guardian troops, who believe the cyborgs may be staging incidents to reclaim their former relevance. Surrounded by threats on all sides, Joe and his comrades abandon their retirement and plunge into a new war. The story explores the futility and tragedy of war, the darker side of imposed utopia, and the difficult choice to fight again for a world that may no longer trust them.