The event of three hundred million yen~ Final mystery in showa period!
S1E1
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Detective Keita Kurokouchi (Tomoya Nagase) continues to extort money from politicians whom Keita Kurokouchi has information on. By using his information he is able to crack unsolved cases. Rookie Detective Mayo Seike (Ayame Gouriki) is excellent with her job and also a bit naive. She conducts an internal investigation on Detective Keita Kurokouchi, but they become partners and work on cases together..