One day, breaking the peaceful silence of Ayaka City, the giant kaiju, Gurugioboru appears! The giant monster starts to rampage through the city, spitting a heat ray from his mouth. Two brothers, Katsumi and Isami try and escape, but suddenly they are both cornered! Just then, the Rube Gyro and Rube Crystals appear before them! The two brothers will use these items to transform into the giants of light known as Ultraman!
兄弟ウルトラマン、はじめます！平和な街、綾香市に突如現れた怪獣、グルジオボーン。セレクトショップ「クワトロM」を経営する湊ウシオの息子、湊カツミとイサミ兄弟も、炎を吐く怪獣の大暴れに巻き込まれてしまう！絶体絶命のピンチを迎えたその時…。ウルトラマンに変身する力を得た兄弟、そしてその家族の物語が、今、幕を開ける！
