Kamen Rider Build The Movie: Be The One (2018) Characters, Setting & Themes Explained

The movie takes place in Nascita, a newly formed Japanese city-state created after a devastating civil war. Much of the action unfolds in a crowded stadium during a tense inauguration ceremony and in a secure government facility where political power plays and Fullbottles are controlled. The setting blends urban governance with public spectacle, highlighting the conflict between the rulers and the Kamen Riders.

• nascita
• stadium
• government facility
• japan
• touto
• hokuto
• seito

The movie is set in a post-civil war era in near-future Japan. After the devastating conflict between the three regions of Touto, Hokuto, and Seito, the governors attempt to reunify Japan. This timeframe emphasizes political upheaval, rapid technological advances, and a society on edge as old loyalties are tested and new power structures form.

• post-civil war
• near-future
• japan
• time period
• reunification

Kengo Inō is the newly installed governor of Touto and a member of the Blood Race, an extraterrestrial species aligned with the alien mastermind Evolto. He uses propaganda to turn the public against Kamen Rider Build and weaponizes fear, making people believe Riders are threats to the state. He orchestrates events from behind the scenes and pursues the Pandora Box to further Earth's destruction.

• kengo ino
• blood race
• governor
• evolto
• propaganda
• touto

Evolto is the alien mastermind whose plans drive the crisis in the movie. He manipulates both the governors and the Kamen Riders to sow chaos, aiming to destroy Earth via the Blood Race and the Pandora Box, just as he has done to other planets. His confidence and intellect make him a formidable foe, constantly shifting the battlefield with deception and power.

• evolto
• alien
• blood race
• pandora box
• destroy earth
• mastermind

The movie explores three central themes: Power & Control, where new governors manipulate public fear and perception to consolidate power; Duty & Sacrifice, where characters struggle between personal loyalties and the greater good; and Identity & Fusion, where blending powers and identities becomes essential to stopping an existential threat.

• themes
• power and control
• duty and sacrifice
• identity and fusion
• politics

Identity & Fusion refers to how the characters blend their powers and identities to confront an existential threat. The Cross-ZBuild fusion, where Sento Kiryū and Ryūga Banjō merge their powers, symbolizes how collaboration can redefine what it means to be a Rider. Evolto's manipulation tests who the characters are when their powers are pushed to the limit, forcing them to question their identities.

• identity fusion
• cross-zbuild
• sento kiryu
• ryuga banjo
• rider powers
• collaboration

The Power & Control theme shows how new governors manipulate public fear and perception to consolidate power after the civil war. The populace is steered to view Kamen Riders as enemies, turning mass support into a tool for political ends. The plot reveals the dangers of governance that suppresses dissent through propaganda and coercion.

• propaganda
• governors
• fear
• political power
• dissent
• rider threat

Misora Isurugi is a young girl saved by Sento Kiryū who becomes a symbol of innocence amid the political turmoil. Her presence motivates the Riders to push through fear and suspicion. Captured during the Nascita crisis, she remains a beacon of hope around which allies rally, representing what the heroes are fighting to protect.

• misora isurugi
• innocence
• capture
• hope
• Symbol
• rally point

The Blood Race are an extraterrestrial species related to Evolto who have infiltrated Earth's leadership. The governors of Touto, Hokuto, and Seito are secretly members of the Blood Tribe, and they intend to destroy Earth as they have done to other planets. They orchestrate attacks on Kamen Rider Build, manipulating friends and allies to achieve their destructive goals.

• blood race
• blood tribe
• extraterrestrial
• governors
• alien invasion
• destroy earth

Kamen Rider Build is the identity of Sento Kiryū, the main protagonist who fights to protect friends and innocents after the governors crack down on Riders. He exposes the political plot by hacking a government database and reveals the truth about the Blood Race and Evolto. He reaches new heights by merging Fullbottles to form Cross-ZBuild, confronting the larger threat to Earth.

• kamen rider build
• sento kiryu
• fullbottles
• cross-zbuild
• protagonist
• hero

Ryūga Banjō is a key ally who fights as Kamen Rider Cross-Z. His loyalty is tested as he becomes entangled in Evolto's schemes and is used as a pawn by the governors, eventually even betraying Sento due to manipulation. He battles to reclaim his autonomy and plays a crucial role in the final clashes against the Blood Race and Evolto, ultimately reconciling with Sento.

• ryuga banjo
• cross-z
• ally
• best friend
• betrayal
• evolto manipulation

Ryouka Saiga is the governor of Hokuto who becomes Scissors Lost Smash, a ruthless enforcer against dissent. She subdues Misora and Sawa during the Nascita escalation and embodies the cold efficiency of the state's hardliners. Her authority is challenged as the Riders peel back the layers of control behind her actions.

• ryouka saiga
• scissors lost smash
• hokuto governor
• enforcer
• hardliner