Two brothers, Minato Kokai, who works at the store run by his father, and Minato Isamu, a college student, live with their sister and father. Suddenly, they encounter an unknown giant creature (monster) that appears in the city! One day, the two brothers obtain the Rob Gyro and Rob Crystal; with the power of R/B Gyro and R/B Crystal, the two transform into Ultraman! The battle between Ultraman Rosso and Ultraman Blu begins!