During the first half hour of the movie I was thinking about the corruption of politics in large cities -- mass politics or better, mob politics. How has East Asia fared under modern democracy? Not well, I would think, even if the alternatives would have been worse.
Then there was the display of rigid social hierarchy based on seniority in age (and supposedly experience, but not necessarily merit). Or it could be bad experience and bad judgment, as exemplified by Hilary Clinton. Can South Korea do away with that social hierarchy and remain (neo-)Confucian? More on that when I finish my post on democracy in China (and East Asia).
While there is a hint to corruption in politics and the legal system, the movie is probably not realistic in its depiction of that corruption. (There are probably better, more realistic movies that deal with the partnerships between politicians and gangsters.) By the last 30 minutes I was sitting to the end, with the wrong kind of stamina. There are no clear good guys in the movie; even those who are interested in bringing down the corrupt mayor have questionable motives, and it is suggested that they are merely following orders from another faction jockeying for control. It's just a lot of evil that ends in a lot of death. Not an uplifting movie, though this is not abnormal for Korean cinema. Does the story qualify as a tragedy? And even if it did, would it be worth watching? I am inclined to say no.
The best part of the movie for me? The use of Robert Plant's arrangement of "Satan Your Kingdom Must Come Down"