I have to say this movie has inevitably reminded me of many movies and TV series: Insomnia (2002), Jesse Stone: Lost in Paradise (2015), True Detective (2014), Fargo 2014), and some great Scandinavian TV series, such as The Bridge, The Killing, Wallander, Border Town...ect., etc. The noir atmosphere are pretty similar and strong. I'm amazed to see that a Chinese movie could be on par with those that I've mentioned above.
This film was well made with great directing, great cast, great camera technique, great subtle scores. The leading male actor is one of the A-list actors, a brand name ensuring better or even the best films if he was in it. The leading female actor is also very very good with profound, unpretentious, natural acting talent. This was a tough acting performance for the leading actor since he got to do a lot of actions in the endless downpour rain, not an easy money to earn for such tough acting.
This is a film with very dreary, suffocating, gray, downcast, depressing atmosphere. Nobody was happy in this film, a struggling generation in China. It's a romance going nowhere and ended up so cruel, with serial killings as the background at a blue-collar steel manufacturing factory in a 3rd or even 4th class of a city in China. The rain seemed to nonstop like what we experienced in Portland or Seattle, but in a city in China, it just looked so throwback hopeless and frustrating, most of the residents there just like what those young people in those harsh, poor and boring towns or small cities in the mid north or south of United States, dreaming to get out of, either going to the west coast or to New York; here in that miserable factory town, people were dreaming moving to Hong Kong or elsewhere. When the factory finally and suddenly closed, all the basic hopes of the people working or living there died together with the city, exactly like Flint, Detroit, Buffalo....and other cities in America where people and business all depended on those sole factories, once they closed or moved away, everything died.
The serial killings might seem to be the main plot but it's what the guy who depended on it to keep investigate, felt alive and hopeful. When the real serial killer was dead, the killings actually stopped, but that guy didn't know so he still pursuit it with his own interpretation. He forgot to grasp the love at hand, only focused on a big-case to be solved by him and him alone. His self-indulgent blindness cost him a lot to lose and without anything to gain in the end. A small potato among the 1.4 billions....