Other Title: 仮面ライダービルド-悪魔のサイエンティスト, Kamen Raidā Birudo-Akuma no Saientisuto
Summary: According to Tatsuya’s testimony, the allegations surrounding Katsuragi
Takumi’s murder now turns towards Sento! He revealed that Taro Sato,
Sento’s former self, was visiting Katsuragi’s room on the day of the
murder. Ryuga, who is aware of the facts, is skeptical about the murder.
The man who has hidden himself until now may be the real culprit.
Ryuga, who interrogates Sento, ends up getting nothing of value from
him. It is just then when both Itsurugi’s make a sudden proposal. “Maybe
you should be investigating Katsuragi Takumi instead.” The search for
discovering Katsuragi Takumi begins, and it leads them towards Hokuto…