Kagemitsu Hazama is the former husband of Mio Hazama and the father of Black Jack who left them and escaped to Macau, China with Renka Hazama (Kagemitsu's new wife) for unknown reasons, but his actions are explained in the Black Jack 21 series.
In chapter U-18 Knew of the manga, it is revealed that he actually lives in Hong Kong with his new wife.
Kagemitsu is an elderly man with white hair, gray eyes and a white mustache.
When he was young, he was a handsome young man with black hair and but he had no mustache.
Kagemitsu is an intelligent and dedicated person like Black Jack (Kagemitsu's son) who worries so much about his family that he was forced to stay in Macao, China with his Renka Hazama, fearing that the organization of the Noir Project would persecute them.
Kagemitsu works as a hospital staff in a New York hospital who met Mio Hazama who also works in the same hospital as a nurse at the NY hospital. He left his job and decided to join the Nior Project, a secret project in which the world's celebrities also participated. One day, he reunited with Mio once again after returning to save her friend's wife, giving her a mechanical heart that she created in the project. In Central Park, she confesses her love to Mio and went to Japan to get married and Black Jack was born. After refusing to resume Project Noir, the organization that threatens to place a bomb on the beach, where Black Jack and Mio were. The bomb exploded, almost killing them and Kagemitsu was forced to flee to Macao, China with his new wife, fearing for the safety of his family.
In China, Kagemitsu started a new family with Renka Hazama (Kagemitsu's second wife) and he was reunited once again with Black Jack and asked him to operate on his wife's face. During a father and son conversation, he lied by saying that he doesn't love Mio for the sake of protecting his family for 21 years. In Episode 15, he fell into a coma for a few days and passed away soon after.
- The name Kagemitsu means "shadow" (影) (kage) and "three" (三) (mitsu).
- Kagemitsu's surname Hazama means "narrow space" (間).