Based on the live action works by Shotaro Ishinomori. Jiro, a humanoid robot gifted with the 'conscience circuit' enabling him to simulate real emotions and distinguish between right and wrong. As Jiro struggles with his dark side, as well as an unsympathetic society, he protects his creator's daughter Mitsuko and her little brother Masaru from the evil Professor Gil. The saga continues in Kikaider 01 as fate brings Jiro into an alliance with his brother Ichiro to stop all evil abound. The stage is set at a conclusive battle as Jiro is once again reunited with Professor Gil!