In college studying archaeology, Dai Sawamura deciphered the figures on the Nazca Plain in Peru. Impressed by this feat, the Galactic Union Police recruited him and trained him to be Earth's third Space Sheriff, after which he was given the code name 'Shaider' in memory of an ancient warrior who defeated the villain Emperor Kubilai and brought down the Fuuma Empire 12,000 years ago. The Empire, upon learning of the appointment of Dai as the new Shaider, plots to annihilate him in order to conquer Earth once again.
