At 24 years old, Shirou was the pilot of the first Japanese space shuttle. During the first assault by Neo Empire Gear on Technotopia 21, he was caught in the crossfire and ran into Bio Robo. Meeting Peebo, he was given a Techno Brace and became Red1.
When the Bio Robo broke down, he had to run back to Biobase to grab a spare circuit. On the way back to Bio Robo, he became aware of his ability to speak with animals. He recruited a team of animal informants to inform the team of Neo Empire Gear's activities.
He grew up believing that his father was dead. However, after meeting Professor Shibata, even he is not so sure. In Episode 47, when Shirou saves his comrades from collapsing, he was hit by the collapsed rock, unconscious only to be saved by Professor Shibata and both end up trapped. Professor Shibata wakes him up and also calling his name which he remember the words from his childhood.