Chou no Rikigaku ~ Keishicho Satsujin Bunsekihan

A wealthy man is brutally murdered at home and “blue flowers” are arranged in his neck which has been slit open. Detective Kisaragi Toko (Kimura Fumino) from the Eleventh Section of Tokyo Metropolitan Police Department's First Investigative Division has to tackle her most difficult case. The man’s wife Mayumi has disappeared and an email hinting at her whereabouts is addressed to a newspaper from the criminal who calls himself Cluster 16. With Toko’s most trusted partner, Takano Hideaki (Aoki Munetaka), due to transfer to the Public Security Bureau in a few days, the responsibilities and hopes for her grow. Contrary to expectations, the investigation of the case runs into difficulty and Toko’s impatience and anxiety mounts at what seems to be a dead end.

Synopsis: JDrama Weblog