Ep. 4: Narihisago kembali untuk menyelidiki pembunuh tiruan Gravedigger sementara Haruka Kazuta muncul.

Following the suicide of the Pyrotechnician, Narihisago is placed in solitary confinement and members of the investigation team feel on edge over his actions. However, an attempt to find a replacement detective proves unsuccessful, and the team is forced to work with Narihisago again. The target is the Gravedigger serial killer, who buries their victims alive and livestreams their dying process. Sakaido discovers the killer is a depressed and lonely man from the victim's neighborhood, but Kazuo realizes he is a copycat killer and the real serial killer remains at large. The police capture the copycat killer, but arrive too late to save the victim. Back in prison, Momoki questions Narihisago about his killing urges, but reassures that they are still friends. The episode ends with Hondomachi being suddenly kissed at the scene of the copycat Gravedigger's crime scene by Haruka Kazuta, a missing man who was a victim of the Perforator killer. (Source: Wikipedia)
Episode
- Ep. 1 · Sakaido terbangun di sumur Perforator setelah Hondomachi diculik oleh pembunuh berantai.
- Ep. 2 · Sakaido bertemu John Walker sementara Hondomachi mengatur penyelamatan dirinya sendiri dari Perforator.
- Ep. 3 · Pembunuh berantai ahli kembang api menggunakan kembang api untuk menembak orang-orang yang tidak bersalah sebelum akhirnya ditangkap.
- Ep. 4 · Narihisago kembali untuk menyelidiki pembunuh tiruan Gravedigger sementara Haruka Kazuta muncul.
- Ep. 5 · Identitas Kazuta sebagai Gravedigger terungkap, memicu ledakan fatal dan terkuaknya Inami sebagai dalang.
- Ep. 6 · Kematian Kazuta dan Investigasi terhadap Identitas John Walker
- Ep. 7 · Hondomachi menyelidiki Narihisago dan Kiki Asukai sementara Momoki dituduh atas nama John Walker
- Ep. 8 · Togo memimpin misi penyelamatan untuk mengekstrak Hondomachi dari sumur id Kiki Asukai sementara Momoki menghadapi interogasi polisi.