Archeology student Dai Sawamura continued his father's research regarding the Nazca Lines. Believing that it contains a message, he journeys to Peru to investigate further, leading him to a cave in Easter Island where he discovered an altar, suddenly he was flash with a high concentration of light knocking him unconcious. Commander Qom of the Galactic Union Police impressed with Dai's determination, intelligence & strong will deemed him worthy and recruited him to become a Space Sheriff. Fuuma a religion from the Fushigi dimension launched an attack on several planets & destroyed anyone who opposed their plans. Qom deputized all training cadets and ordered them to return their home planet to defend them against the impending threat. Dai Sawamura was given the code name SHAIDER and was joined by fellow cadet Space Sheriff Annie from the Planet Mount which was destroyed by Fuuma. Together they returned to Earth to battle Fuuma and thwart their conquest.
Fuuma from the strange realm led by their Emperor Kubilai began it's galactic conquest, Commander Qom of the Galactic Police immediately deputizes all trainees as Space Sheriffs to fight against the impending threat. Cadet Sawamura Dai is deployed to his home, Earth and given the code name Shaider. Aiding him is Female Space Sheriff Annie who vowed vengeance against Fuuma for destroying her home world.
Fuuma uses the Shigi (Strange) Song to make animals ferocious and having children give up their beloved pets, causing them great anguish. Shaider & Annie steps in to stop the evil plans of Fuuma.
High Priest Poe uses the hypnotic effects of the Strange flowers on Annie, making her believe that her family is alive and Shaider has hurt them.
A strange beast disguised as a witch, grants magic to children to make them transform into animals, in reality they are replaced by Fuuma's creatures. The children are kidnapped and given chromosomes that will transform them into Fuuma's beasts permanently.
To stop the development of society, Fuuma establish the church of MujiMuji, it's doctrines turned hard working people into sloths Youko a friend of Dai was kidnapped and forced into the cult's teaching.
After eating the strange cuisine's food, a bullied young kind boy developed telekinetic powers. He uses this power to get back on all those who made fun of him, becoming vengeful and arrogant. Shaider investigates the sudden change of the boy's attitude.
