A mysterious phenomenon occurs in a hot spring in Beppu. It foreshadows the appearance of the legendary giant monster Bugon, a guardian deity who has been watching over Oita since ancient times. The locals band together to stop the rampaging Bugon, who releases hot spring water from his mouth, but...
Kujirai Taichi has been selected to be the leader of the staff at the Taiji Municipal Whale Museum. Despite enlisting the aid of Shiraishi Yui who came from a Tokyo aquarium, and the museum curator Mashiba Nozomi, Taichi and the staff are perplexed by the low turnout of visitors. Then Taichi hits upon the idea to hold a staff created "whale festival" in order to generate hype for the museum. One day however, the "whale festival" is in danger of being cancelled as the opening quickly approaches.
A young man becomes the giant hero Ultraman Orb, a warrior of light, to battle monsters and aliens threatening Earth using the powers of his many predecessor guardians.