Kamen Rider Build

That One with the Best Match (1x1)

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A mysterious object known as the Pandora Box was brought back from Mars. In effect, Japan was divided into three by giant walls produced from the box. 10 years have passed since that day. This story takes place in one of the city capitals, Touto. Mysterious organisms known as Smash are terrorizing humanity. A physicist saves people from the Smash and pursues the mystery hidden within the Pandora Box. His name is Sento Kiryu. People call him... the Kamen Rider.