|4,000 years ago in China, a form of Kempo martial arts referred to as Beast-Fist (JyuKen) style was developed. Whoever practices this fighting style could mimic animal abilities as well as reach spiritual peace. Masters of the craft become a Beast-Man form. There was ten masters but rebellion broke loose and three (Sankenma - Three Fist Demons) defected from them and established the Confrontation Beast-Fist Akugata that focuses on the principles of natural selection, that only those strong enough can survive the harsh and inhuman training while fully mastering the Akugata's fighting styles. The last seven (Kensei - Fist Saints) created the Fierce Beast-Fist Beast Arts, a discipline that enchances the human body. It is now taught by Grand Master Shafu using a sports goods company named SCRTC ('Scratch') as a front. A former student of ShaFu, user of the RinJyu Lion-Fist, Rio, creates the Conforntation Beast Hall with intent on controlling the world with an army of the undead. Shafu has been training two youths Ran Uzaki and Retsu Fukami to fight the Confrontation Beast Hall. Along with a boy raised in the forest, Jan, form together the Gekiranger to confront Rio and his army of kyonshi soldiers. The Gekiranger train and learn new techniques by practicing ordinary skills such as cleaning floors, playing the piano, fishing, painting, etc.
Through their lessons and training, the triad learn from the other Kensei and gain new GekiBeasts. Retsu's long-lost brother Gou Fukami, who was once Rio's friend, returns and becomes GekiViolet. His power is the Shigeki, where anything is possible, but he was also cursed by a flawed technique to change into a werewolf. The mysterious Ron exerbated Gou's transformations, until Bae, who also has a flawed technique, helped Gou rid of his wolf side. After they are content being a quartet, they are informed they must have a fifth member GekiJyu Rhino-Fist user Ken Hisatsu, GekiChopper. Rio disobeyed the Kenma and went to the Geki Sacred Ground, where he and Mele were confronted by the Kensei. Rio and Mele had the SouJyuTo, which Mele stole from Ken, who was entrusted with it. Once they found SaiDain, the GekiSoul of the creator (Bruce E.) of JyuKen, the seven youth were sent to the past. When they returned, they found the Sacred Ground brunt by the Kenma and the Kensei all fused together into a rock. Ken, who promised to protect the Scared Ground, he showed his true dedication enough for SaiDain to come alive. SaiDain poured on the seven the Full Beast Bloom, which made them stronger. Rio realized he could suprass the Kenma. Once the Kenma were destroyed, Ron lured Rio and Mele into a new fighting school, the GenJyuKen. Ron revealed himself as his GenJyu Dragon-Ken beastman form and introduced other GenJyuKen users. Mele went through a ritual to become GenJyu Phoenix-Fist user.
The Opening Sequence does not change until Episode 28, highlighting GekiViolet, GekiChopper, Ron, Super Gekiranger, the Kensei (Fist Saints), ten Gekibeasts, GekiToujaWolf and GekiFire.