Archaeologist Senjirou Shiba unearthed a bronze bell artifact, revealing evidence of the ancient Jamatai Kingdom and its ruler, Queen Himika. Anticipating the kingdom's resurgence, he researched countermeasures and integrated the bell's power into cybernetic technology. He used this technology to save his mortally injured son, Hiroshi Shiba, transforming him into a cyborg capable of piloting the super robot Jeeg. This focus led him to neglect family responsibilities, a point he later acknowledged.

Attacked by Jamatai forces seeking the bronze bell, he sustained fatal wounds. Before dying, he transferred his consciousness and memories into the Build Base defense facility's computer system. In this digital form, he continued guiding Hiroshi and Miwa Uzuki, pilot of the support jet Big Shooter, against Queen Himika's forces. His uploaded intellect provided strategic and technical support for Jeeg's operations, acting as a posthumous mentor.

In the continuity of Kotetsushin Jeeg, a narrative retcon reimagines his fate. Here, he survived the initial attack and escaped Kyushu before a dimensional barrier sealed the region. Using a second bronze bell, he developed a new Jeeg unit and oversaw construction of a new Build Base overlooking the sealed zone. As commander of this facility, he directed operations against the resurgent Haniwa Empire 50 years after the original conflict, coordinating the new Jeeg pilot Kenji Kusanagi, support personnel, and defense systems like the Build Angels squadron. He maintained his scientific duties, analyzing threats and deploying countermeasures.

Senjirou Shiba reflects persistent dedication to combating the Jamatai/Haniwa threat across timelines, whether through physical research, digital guidance, or strategic command. His computer incarnation in the original storyline performed a heroic sacrifice by attacking the enemy fortress Orochi, while the living version in the sequel continued his vigilance until the final confrontation with the Haniwa Empire.