Brothers Ultraman begins now! The peaceful city of Ayase is suddenly attacked by a monster, Grigio Bone. Select shop "Quattro M" staff and sons of Minato Ushio, the Minato Katsumi and Isami brothers, are embroiled in this fire-breathing monster's rampage. When they thought it were the end... gaining the power to transform into Ultraman, the story of the brothers and their family begins...

While younger brother Isami is ecstatic about his new powers, elder brother Katsumi on the other hand was in fear of this great power.

The three siblings visit President Makoto Aizen of the enterprise "Aizentech" in Ayase city, and enjoy experience the most advanced technology. There, they are surprised to learn that their missing mother had been working together with President Aizen on some research in the past. Meanwhile, Gargorgon appears in the city.

Katsumi was a well-known pitcher during his high school years. He unwillingly turned down the offer to play professional in order to support his family, and now willingly trying to set a retirement match for his sandlot baseball team's head coach. But his injuries from previous battles affects his pitching, and head coach gives him a few words.

Yuha Ninomiya, with her passion for flight, continued to fail and injur herself with her wings invented in college. Nagisa Isami gets involved with his classmate's reckless challenge and both aim high for the sky, until storm-producing monster Guebasser appears. Go fight, Isami (Ultraman Blu) with your new power of wind!

Komane is back! Her name is Kaoru Komaki. an ex-cop who Katsumi and Isami were very fond of as children. Friend and foe, they are excited to meet for the first time in 4 years. But soon enough, she is captured by Mecha Gomora. How will the brothers face this strong and sturdy monster?