Aruto Hiden is the main protagonist of Kamen Rider Zero-One. He is a lighthearted and optimistic young man who inherits the role of CEO of Hiden Intelligence, a leading robotics company. Aruto transforms into the titular Kamen Rider Zero-One, fighting against rogue Humagears and the terrorist organization MetsubouJinrai.net. Throughout the series, he strives to bridge the gap between humans and AI, believing in a future where both coexist harmoniously. His journey is marked by personal growth and a deepening understanding of the responsibilities that come with his dual roles.