Kamen Rider S27 E21 Chase the Mystery!

Emu and Hiiro learned from Poppy that Kuroto was the one who had suggested Emu to CR. Meanwhile, a police detective is investigating the Zero Day case, causing him to interrogate Kuroto's father, Masamune. During the investigation, he gets infected by the Game Illness. In order to save him, Emu confronts Masamune.