In the Name of Ultraman

Brothers Katsumi and Isami have completely lost their first fight against Ultraman Orb Dark! Ultraman Orb Dark slowly starts to win over the hearts of the people of Ayaka City after pointing out Ultraman R/B's inexperience at being heroes. What do the brothers discover when they look into their own immaturity? What is the true aim of Ultraman Orb Dark?