|Peace was restored to Earth after Kamen Rider Black defeated Gorgom. With nobody else by his side, Minami Kotaro was taken in by the Sahara family. He was given a job as a helicopter pilot for the Sahara Industry. Kotaro also had a girlfriend named Reiko Shiratori, a photo journalist. It was about less than a year after the defeat of Gorgom before a new evil group started attacking the earth. The Crisis Empire knew that there was an obstacle in their quest to invade planet Earth, and that obstacle came in the form of Kamen Rider Black. During their first encounter, Crisis outsmarted Kotaro by having their Skull Devils to restrict his movements, making him unable to transform into Kamen Rider Black. Kotaro was captured and was brought to Crisis' spaceship. He was given two choices: either he joined forces with them or die! Kotaro refused to join forces with Crisis. As a result, he was thrown into outer space. Crisis attacked Kotaro by shooting beams at him and one of them managed to go through his body, splitting his Kingstone into two. As soon as Kotaro was left motionless, the sun started to rise and the split Kingstone reacted to the light. Kotaro fell back to the earth and caused a huge explosion. Despite the explosion, Kotaro was still alive. He was automatically transformed into another cyborg. Due to the split of the Kingstone, Kamen Rider Black had changed his form and Kotaro officially declared himself as Kamen Rider Black RX. As Black RX, his mission was to stop Crisis Empire and to save the earth.