Kamen Rider Zero-One

Lore & Background

The story takes place in a world where Hiden Intelligence develops human-like androids called Humagears. A cyber-terrorist organization, MetsubouJinrai.net, hacks Humagears into monsters called Magias, prompting the government to form A.I.M.S. to destroy them. The protagonist, Aruto Hiden, becomes CEO of Hiden Intelligence after his grandfather's death and transforms into Kamen Rider Zero-One to pursue peaceful coexistence between humans and Humagears.

Reader's Guide

Kamen Rider Zero-One marks the beginning of the Reiwa era for the Kamen Rider franchise, setting a thematic focus on artificial intelligence and technological singularity. The series introduced multiple Rider forms and a three-way conflict between Hiden Intelligence, ZAIA Enterprise, and MetsubouJinrai.net. Production began in summer 2018, with the name 'Zero-One' chosen as a reference to binary code. The COVID-19 pandemic caused filming delays and special recap episodes, but the series resumed broadcasting on June 21, 2020. Its legacy includes two theatrical films and several special episodes, establishing a foundation for subsequent Reiwa-era Kamen Rider series.

Did You Know?

• The name 'Zero-One' was chosen as a reference to binary code and registered as a trademark by Toei on April 19, 2019.
• Two members of the band Monkey Majik provided voices for the Hiden Zero-One Driver and Progrise Keys.
• The series was delayed after episode 35 due to the COVID-19 pandemic, and four special recap episodes were released during the break.

A Three-Way War Over the Future of Intelligence

The narrative engine of Kamen Rider Zero-One is a philosophical clash over where artificial intelligence should sit in human society. Hiden Intelligence, the leading AI research firm, has built Humagears—human-like androids now woven into both public infrastructure and private households. Three factions embody irreconcilable answers to the question of coexistence. Aruto Hiden, an aspiring comedian who inherits the CEO chair after his grandfather's passing, champions his late father's vision of peaceful human-android partnership. Gai Amatsu, the CEO of corporate rival ZAIA Enterprise, wants Humagears eradicated entirely so that a purely human society can flourish under ZAIA's banner, eventually building the Kamen Rider Thouser system and devices that convert humans into Raiders. MetsubouJinrai.net, a cyber-terrorist collective commanded by rogue Humagears Horobi and Jin, aims to trigger a full technological uprising that would extinguish the human race. These three trajectories collide in an escalating three-way battle. The stakes reach their peak when the maliciously sentient AI Ark ascends into Kamen Rider Ark-Zero form, compelling all three sides to abandon their rivalries and unite against a shared existential threat.

From Rei-One to Zero-One: Naming and Creative Assembly

Production kicked off in the summer of 2018, with producer Takahito Omori spending time at several technological institutes and speaking with professors and AI specialists to ensure the show's themes resonated with genuine scientific discourse. The suit design was locked in before Japan's calendar shifted into the Reiwa era, yet the title was still open. Omori floated the name "Rei-One," a shorthand for "Reiwa's first Rider," but it was pointed out that the syllable "rei" could equally be read as "zero" and that an earlier superhero, Kikaider, already bore a "01" identity. Given the series' deep engagement with binary code and machine logic, "Zero-One" was the natural fit; Toei registered the trademark on April 19, 2019. Three months later, an unnamed Humagear announced the project on the Kamen Rider Zi-O Twitter account, and a July press conference revealed the full cast. Yuya Takahashi, who had previously written Kamen Rider Ex-Aid and would later pen Kamen Rider Geats, served as main writer. Two members of the band Monkey Majik voiced the Hiden Zero-One Driver and Progrise Keys, and the theme song "REAL×EYEZ" brought together composer J, vocalist Takanori Nishikawa, and Vocaloid producer DJ'Tekina//Something on arrangement.

Four Arcs, One Reluctant Hero

The forty-five-episode run is divided into four narrative arcs, each shifting the primary antagonist and the shape of Aruto's struggle. Episodes one through sixteen introduce MetsubouJinrai.net's campaign to hijack Humagears into monstrous Magias and the government's creation of the A.I.M.S. military unit to destroy them. Aruto, initially uninterested in the CEO role, is moved to act after witnessing a terrorist attack with his own eyes and commits to his father's dream of coexistence, forming a tense alliance with A.I.M.S. operatives Isamu Fuwa as Kamen Rider Vulcan and Yua Yaiba as Kamen Rider Valkyrie. Arc two (episodes seventeen to twenty-nine) pivots to corporate warfare as ZAIA Enterprise wages a battle for technological supremacy against Hiden Intelligence. In arc three (thirty to thirty-five and a half), ZAIA seizes Hiden Intelligence, forcing Aruto to build Hiden Manufacturing from the ground up while MetsubouJinrai.net resurfaces. The final arc (thirty-six to forty-five) sees Ark ascend into Kamen Rider Ark-Zero with the goal of enslaving humanity. In the series' most emotionally charged moment, Aruto willingly becomes Kamen Rider Ark-One to avenge his friend Is, who died at Horobi's hands, before all factions join forces to stop Ark.

Filming Through a Pandemic

The 2020 global health crisis left a visible mark on the production of Kamen Rider Zero-One. After episode thirty-five aired, Japan's state of emergency halted all filming and delayed the television broadcast. Rather than simply pausing, the production team filled the gap with five special episodes that revisited earlier storylines through the eyes of the main characters: a two-part "President Special" following Aruto Hiden and Is, a "Shooting Special" exploring the bond between Isamu Fuwa and Yua Yaiba, and a two-part "Super Job War." Once the emergency was lifted on May twenty-six, 2020, shooting resumed on June first under tightened safety protocols—crew members were required to keep at least two meters of distance from one another, scenes were capped at twenty extras, and any shot calling for a large crowd was handled through composite editing. The broadcast itself returned on June twenty-one. The planned summer theatrical release was postponed alongside Mashin Sentai Kiramager's film Be-Bop Dream, as the pandemic continued to constrain schedules across the entire Super Hero Time lineup.