Professor Isaac Gilmore is a scientist and one of the main supporting characters in Cyborg 009 Call of Justice. He is a leading authority in bioengineering who previously served as the head scientist of the 00 Cyborg program for the Black Ghost organization. In that capacity, he was a dutiful worker who kept his growing distrust of Black Ghost's plans to himself while carrying out the conversion of nine kidnapped people into experimental cyborg soldiers. During the process, he witnessed the agonizing pain the subjects endured as they were transformed, especially in the later stages of the program, and was profoundly disturbed by it. Recognizing that he had been deceived by the organization, he turned against Black Ghost and helped the cyborgs escape, allowing himself to be taken hostage by them during the escape.

Since leaving Black Ghost, Gilmore has devoted himself to supporting the nine cyborgs as their advisor, strategist, and technical lifeline. He is responsible for maintaining, repairing, and upgrading their mechanical bodies, and he helps them understand the capabilities and limits of their enhancements. His expertise makes the team reliant on him for mission planning and for guidance in using their powers effectively. He carries a strong sense of responsibility for the suffering the cyborgs endured, and he regards them as his own children, caring for them with the attentiveness of a father figure. The cyborgs, in turn, see him as an understanding guardian and a trusted leader of their operations.

Gilmore's role in Call of Justice builds on this established position. When the journalist Lucy Davenport brings a warning about the future and confronts Gilmore and the cyborgs about their past, the team is compelled to regroup and return to action. Gilmore stands alongside them as they face a new threat brought by the storm and its source, the Cowboy. His presence anchors the team during this renewed conflict, just as it did in their earlier battles against Black Ghost.

In terms of personal development, Gilmore's arc moves from complicit scientist to remorseful defector to devoted protector. His initial obedience to Black Ghost gives way to open opposition once he understands the true nature of the organization and the harm done to his subjects. His motivation is rooted in atonement: he feels bound to stand by the people he helped create and to ensure their fight for justice continues. His notable abilities are scientific rather than combat-oriented, but his command of cybernetics and his intimate knowledge of the cyborgs' construction make him indispensable to the team's survival and effectiveness.