A young man sets foot in Akebono City, a town likely to be anywhere in Japan. A newly appointed police detective, Kenji Narukami. The town is under martial law. A horde of demons was pouring in and causing big panic in the city. Kenji, who stands alone, witness policemen running away at first sight of demons, also sees S.H.O.T.'s warrior, RyuGunOu, wiping out the demons thus regaining peace to Akebono City. However, a further threat to the town appears, the attack by Demon Beast Reptolilix! Kenji bravely challenged the battle...

The people of Akebono City are suffering from the evil organization known as Jamanga. They are collecting the negative energy generated when people feel fear and anxiety for the resurrection of the Great Demon King. On the other hand, Kenji is taken to the secret base of S.H.O.T., an organization that fights against Jamanga. Therefore, he vows to fight as S.H.O.T.'s warrior, RyuKenDo, together with the sword, GekiRyuKen, who has the will and can speak languages. At that time, the Plant Demon Beast Giga Flower attacks the town. It's time to use the new key, Fire Key for RyuKenDo!!

Jamanga General, Doctor Worm, arrives with a huge armoured black tank to attack Akebono City! The demons are catching the residents one after another. Kenji comes across a female police officer who shoots and fights with a handgun. It is Ichiko and Ritsuko of the Akebono Police Department, Traffic Division. Kenji is impressed by their determination to protect their city by themselves and transform into RyuKenDo and summon the beast king, Brave Leon. Brave Leon is transformed into Leon Trike. To defeat the armoured black tank, RyuKenDo began to track them using Leon Trike!

Fire RyuKenDo defeated the advanced demon, Tsukaima using his finishing move, Blazing Slash. At S.H.O.T.'s Base, the Madan key obtained from defeating Jamanga's armoured black tank was found to be Aqua Key by The Book of Canon of Light and began to adjust. But they don't know how to use it. On the other hand, Rin pointed out from the people in the city that the stronger RyuKenDo is, the more powerful the enemy will be. Then, the Tsukaima who should have been defeated appeared again. The enemy has challenged the battle with its new flame slashing power!

Kenji, who gained Fire Mode, Aqua Mode, and even the Beast King, is completely ecstatic. Around that time, another General of Jamanga, Jack Moon, appeared in Akebono City, and after searching for S.H.O.T.'s information, people were trapped in a crystal ball! Komachi, a ghost that appears in Akebono City stopped Kenji from facing the fight alone. However, he struggles with the powerful attacks from the proud swordsmen, Jack Moon. An unexpected reinforcement appeared there ...

As a result of analyzing the acquired Madan Key at S.H.O.T., it became clear that it was a key to activate RyuGunOu's new powerful technique, the Dragon Cannon. So in order to acquire the powerful technique, Fudou repeatedly undergoes severe training. In the sky of the city, Jamanga's demon beast, Balloon Gunner, appeared. People who took a beam from Balloon Gunner, made them swells like a balloon and floated in the sky. Fudou, who completed the technique with amazing speed, decided to work with Kenji to defeat the enemy and save people...

Giant iron weights crush buildings and cars. Akebono Police Station is in a state of trouble with the work of Jamanga. RyuKenDo struggles with the attack of the demon beast, Meganōma which can make iron weights fall from the sky. Not even a Blazing Slash can defeat it. So RyuKenDo summons a new beast king! The name is Gorilla Beast King, Fire Kong. However, Fire Kong, who has a lot of pride on the other hand, was hurt by RyuKenDo's words and ran away without listening to orders!!

The river flowing through the town suddenly gets dirty, and the demon beast, Edenoid appears from the water! Pollution spreads in a moment. RyuKenDo and RyuGunOu are fighting the demon, but it escapes too quickly and lost track. S.H.O.T's member, Rin Sakyo, burns hostility at the demon who soils clean water as an act that cannot be forgiven. Rin had memories of her late brother. With her brother trying to protect the river where fireflies can live, Rin headed towards the forest alone for the search where Edenoid is likely to be lurking.

A mysterious giant statue suddenly appeared on the outskirts of Akebono City. S.H.O.T. strengthens vigilance against the disturbing scheme of Jamanga. Meanwhile, Kenji ends up fighting with his partner, GekiRyuKen. Then, a mysterious sound wave was emitted in Akebono City, making people wanted to cover their ear. People begin to suffer. At the same time, GekiRyuKen breaks. To stop the mysterious sound waves, Kenji, who can not transform, endured pain and jumped out to the town!!

An incident occurred in Akebono City where various things were gnawed. People begin to fear at the sight of ancient demon creatures flying in the sky. But, Kenji had a more frightening cause of worry. It is said that his older sister who is scarier than the demon coming for a visit. If he doesn't show his older sister how well he is doing in town, he'll be taken back to the countryside. Kenji, who doesn't reveal that he is RyuKenDo, falls into a pinch. With flying demons appearing here and there, his older sister finally came to town!

In Jamanga's Base, Thunder Key with the strongest magic was fused with a part of the body from Jack Moon, and the clone, Elemoon was born. Elemoon is on the mission of defeating RyuKenDo and is rampaging by shooting lightning everywhere. Kenji and Fudou are powerless against the power of thunder. Devices in S.H.O.T.'s base are also short-circuited due to the influence of overcurrent, and Commander Amachi will carry out unprecedented ground operations. It was a strategy to hunt down Elemoon and capture it in an armoured tank!

The use of unadjusted Thunder Key caused GekiRyuKen to be in a state of shock, and Kenji fell into an inability to transform. In such a case, a tremendous magic wave runs in the town of Akebono City. Suddenly, a huge Jack Moon's Castle that appeared in the sky started the attack. The explosion occurred in various places by the ray which was shot indiscriminately! Hiding in shelters, among the feared people, the old town chairman called for a decision. The people of the town who stood up got on the fighter jet and headed for Jack Moon's Castle.

Kenji and Fudou are staked out in abandoned factories on criminal missions. He finds and tracks the thief, but Kenji falls off the roof. After regaining consciousness, Kenji calls out to RyuGunOu, who is fighting the Tsukaima on the spot. However, he declared that he does not know about Kenji like memory loss. To tell the truth, Kenji went back in time and returned six months ago. It was a time when Fudou was fighting alone. Kenji began to talk about the upcoming fierce match against Jamanga.

A new General of Jamanga, Lady Gold, has boarded the town of Akebono City. Mysterious magic was cast on the Florist, Kaori in her flower shop, and showed an illusion of RyuKenDo slashing Ichiko and Ritsuko. Kaori's sightings spread quickly and the townspeople begin to lose trust in RyuKenDo. Also, Giant RyuKenDo began to destroy the town!! A mysterious black warrior has appeared in front of RyuKenDo who challenge Lady Gold who set the trap.