A young martial artist named Kazuya Oki volunteers for a radical cybernetic surgery as part of the International Space Development Program in the United States. His goal is to become a new kind of astronaut, a cyborg capable of surviving the vacuum of space without a bulky suit, enabling more advanced space exploration. The operation is a success, and he is given the codename Super-1. Before he can embark on his first mission, however, the secret research base is attacked by the Dogma Kingdom, a secret extremist organization from Dark-Nebula B-26. The attack kills all the scientists, and Kazuya only narrowly escapes.

Returning to Japan, Kazuya seeks out his old instructor, the martial arts master Genkai, to train in the ways of Sekishin Shorin Ken (Sincere Shaolin Fist). Through this rigorous training, he learns to control his cyborg body and unlocks the ability to transform into the powerful Kamen Rider Super-1. Determined to avenge the deaths of the scientists and stop the Dogma Kingdom's plot to rule the Earth, Kazuya uses his new abilities to fight as Super-1. His arsenal includes the Five Hands system, interchangeable hand modules on his belt that grant him different abilities like super strength, electrical attacks, and extreme heat or cold, and he rides the V-Machine, a Harley-Davidson motorcycle that can convert into a high-speed jet mode called the V-Jet.

The first major narrative arc pits Super-1 against the Dogma Kingdom and its leaders, the ancient Emperor Terror Macro and his chief general, General Megirl. After a prolonged campaign, Super-1 manages to defeat both Megirl and Terror Macro in battle, seemingly destroying the organization. However, the victory is short-lived. From the ashes of the Dogma Kingdom, a new and more formidable terrorist group emerges: Jin Dogma. This new organization operates with even greater brutality, implementing policies of violence,掠夺 (looting), and destruction. The series undergoes a tonal shift at this point, as the show's time slot changed, leading to the introduction of the Junior Riders, a team of children who assist Super-1, and the Jin Dogma monsters becoming more bizarre, often themed after everyday objects like refrigerators and umbrellas.

Super-1 battles against Jin Dogma's four main commanders: Princess Yokai, Commander Onibi, Doctor Ghost, and Staff Officer Witch, as well as their leader, Marshal Demon. The final episodes reveal that both the Dogma Kingdom and Jin Dogma are ultimately connected, with their leaders being alien beings from the same dark nebula. In a climactic final battle, Super-1 defeats Marshal Demon in his monstrous form, Satan Snake. With Jin Dogma destroyed, Kazuya Oki finally fulfills his original dream: he becomes an astronaut and ventures into outer space, the goal for which he sacrificed his humanity in the first place.