In the aftermath of the Sky Casino's fall, Kunikida's faced with a terrible choice. Ango, Atsushi, Lucy, and Kyoka dig deeper into the secrets hidden within Atsushi's memories, and Rampo proves his worth as the world's greatest detective.
Kamui, the head of Decay of the Angel, has the page. Fukuzawa orders the detectives to destroy it. Ranpo, despite being a wanted person, proudly appears at the press conference, exposing the truth and involving the police.
Kamui's identity's revealed. Facing a formidable enemy, Atsushi fights without a single ally until Akutagawa comes to help. The two devise an attack plan to defeat Kamui using a combination of their special abilities...will it work?
The last member of Decay of the Angels is revealed. Kamui continues to spread chaos. Tachihara entrusts Fukuchi with the information device containing evidence obtained at the Sky Casino, only to face devastating consequences.
Fukuchi's plans and the Agency's attempts to thwart him escalate, and Aya comes face to face with Count Bram. Meanwhile, Nikolai and Sigma move to rescue Dazai and Fyodor from prison, but Nikolai has more than rescue on his mind.
Kenji fights to help Atsushi, demonstrating why he is one of the most dangerous Agency members. Meanwhile, Dazai's machinations within the prison become clearer.
Dazai and Sigma are trapped in a flooding room. Atsushi is attacked by Akutagawa when he attempts to help Aya. During their fight Aya desperately tries to remove the holy sword from Bram.
The final pieces of Fukuchi's plot snap into place, trapping Fukuzawa in a way not even Rampo could anticipate. At the same time, Fyodor and Dazai's deadly game draws to a close.