Kamen Rider Skyrider(1979)

Doctor Keitaro Shido, an acclaimed scientist, has been kidnapped by the terrorist organization Neo-Shocker to exploit his expertise in robotics technology. Desperate to escape, he convinces Neo-Shocker's command to allow him to operate on an injured camper. Explaining that he can turn the camper, Hiroshi Tsukuba into a powerful Neo-Shocker warrior, they allow Doctor Shido to operate. However, he quickly turns the tables on them, transforming Hiroshi, not into a kaijin, but the powerful warrior Skyrider, using his newfound abilities to combat the evil Neo-Shocker menace.