The English cast for the series includes Max Mittelman as Atsushi Nakajima and Kaiji Tang taking on the role of Osamu Dazaki for the series.
The Japanese cast includes Yuto Uemura as Atsushi Nakajima, Mamoru Miyano as Osamu Dazai, Yoshimasa Hosoya as Doppo Kunikida, Hiroshi Kamiya as Ranpo Edogawa, Toshiyuki Toyonaga as Junichirou Tanizaki, Hiroyuki Kagura as Kenji Miyazawa, Yuu Shimamura as Akiko Yosano, Chiaki Omigawa as Naomi Tanizak, Rikiya Koyama as Yukichi Fukuzawa, Kensho Ono as Ryuunosuke Akutagawa, Wataru Hatano as Motojiro Kaijii, Asami Seto as Ichiyo Higuchi and Sumire Morohoshi as Kyoka Izumi.
The anime adaptation was produced by Bones with Takuya Igarashi directing it based on the screenplay by Yoji Enokido.
That man is Dazai Osamu, and he and his partner Kunikida are members of a very special detective agency.