Hitori Shizuka (2012)

A big secret is intertwined with five murders that occur at different times and locations. The first murder is a fatal shooting at an apartment in a residential neighborhood. When senior patrol officer Kizaki, who works near the site, rushes over at the sound of a gunshot(s), his senior Omura has already entered the crime scene. The suspects are narrowed down through legwork and forensics results, but Kizaki feels that there is more to the case. Before long, a girl with some sort of connection to the case emerges..