1300 years ago a meteor struck the Earth leaving a massive crater releasing Grigio Bone (left) and the R/B Brothers (right). They were warriors from planet O-50 sent to stop the planet-consuming monster, Reugosite. Only to lose him and original Rosso and Blu dispersing into R/B Crystals; leave their sister, Grigio (latter known as Saki Mitsurugi).
Ayaka City was home to two teenagers Katsumi and Isami Minato. Katsumi played baseball while Isami was a scientist.
One day Katsumi and Isami was investigating the area then the Kaiju Grigio Bone appeared once again. Isami distracted the monster while Katsumi was rescuing a boy. Isami was at the bottom of the Kaiju ready to squash Isami when Katsumi tried to save him.Then two R/B Gyros and R/B Crystals in front of them and used the R/B Gyros to transform into Ultraman Rosso and Ultraman Blu.Confused by their gigantic size the Kaiju charged at Blu until Rosso fired a Fire bullet at him,after that Blu unleashed a jumping kick but missed after Rosso tried to hit him with a tree but wasn’t affected.They noticed that they were running out of time then changed Crystals they kept fighting until they changed Crystals again and used their Flame Sphere Shoot and Aqua Stream to finish him off.
- Rosso means “Red” in Italian.