Yū Amagi is a slightly eccentric detective who has been assigned to the Twelfth Section of the Tokyo Metropolitan Police Department's First Investigative Division from the Lost and Found Centre. The Twelfth Section is called the "graveyard of detectives" and ridiculed as the "banishment room where hardened detectives who cannot be fired are sent." Its assembled detectives Kōsuke Samura, Takumi Yamashita, Keita Nagasawa, Tamaki Mizuta, and Masatoshi Katagiri are elite and yet oddballs. Amagi appears fixated with time which seems to have no relation with a case. Raising questions about the timelines of the perpetrator and victim derived from the estimated time of death, time of crime, time of alibi, and time limit, he searches for the meaning of "blank time" which arises from this. He obsesses over the weight of every minute and second of time because of some incident.

Noriyuki Higashiyamaas Yuu Amagi
Kana Kurashinaas Tamaki Mizuta
Kotaro Yoshidaas Masatoshi Katagiri
Kinya Kitaojias Shuntaro Domoto
Masahiro Takashimaas Kosuke Samura
Ainosuke Kataokaas Takumi Yamashita
Kosuke Suzukias Keita Nagasawa
Seiichi Tanabeas Yoshiki Ebisawa
Jin Shirasuas Takumi Nonomura
Takashi Tsukamotoas Arata Aoyama
Hiroyuki Yatsu
Kiyoshi Yoshikawa