I have mixed feelings about the ending. As far as endings go, it wasn't a bad one. It tied up almost every loose end (I maintain some scepticism about Oh Ji-hyuk's childhood bogeyman) and even managed to throw in a minor twist just so nobody (the audience included) wallows in any complacency about the complexities and unpredictability of life. I liked that Kang Do-chang's ever expanding family remains intact whether it's those share a roof with him or those that back him up while they're in pursuit of suspects great and small. I imagine too that Oh Ji-hyuk and Jin Seo-gyeong's understated romance will take flight in due course.
While I was relieved to see Oh Jang-tae finally get his comeuppance, there's a part of me that recoils at the thought that it had to be done with a bit of... what I consider to be... legal diddling. It is a somewhat unsatisfying result and not a little frustrating because it seems that the justice system is inadequate to the task of dealing with certain kinds of culprits -- those with powerful connections unless said power is muted in some way or changes hands. However, I acknowledge that without a bit of sleight of hand, Oh Jang-tae would continue to evade the full extent of the law's reach and get what he rightly deserves. Moreover, it is also true that Yoo Jeong-seok and Oh Jang-tae were complicit in the death of Lee Dae-chul and should be held responsible for that. But there's a part of me... maybe an unexpected streak of idealism about the rule of law... a belief that perpetrators should be convicted and sentenced for the crimes that they've actually committed. Nonetheless, the flawed system being what it is, it seems that one has to settle for consolation prizes. Since Oh Jang-tae cheated his way out of being convicted for Yoon Ji-sun's death using his wealth and connections, it does seem fitting on some level that he gets convicted for something ... like the death of Yoo Jeong-seok... that he didn't do due to more blind eye turning. I'm sure some would consider it poetic justice even. It's tragic and terrifying to my mind that the criminal justice system can be so manipulated and that it has to take one sort conspiracy to undo another conspiracy. But the realist in me reluctantly concedes to the thesis and premise of the drama: The only way for the spirit of the law to be reclaimed in this instance is to circumvent the letter of the law.
I don't think the revelation that Nam Guk-hyun dealt Detective Jang Jin-su the actual death blow really changes very much in the scheme of things. He was certainly my original suspect for the late detective's murder. If anything it confirms our suspicion that he was a hopelessly greedy and shady character that was a cancer in the police organization. And of course it spreads the guilt around a little. It doesn't make Yoo Jeong-seok less guilty nor does it mitigate the fact that he did try to subvert the system to his advantage at the cost of other people's lives. At least he recognized his own culpability and did what he could to rectify a situation that he had been party to. It was his statement to everyone that he would pay for his sins by taking Oh Jang-tae down with him. Taking a swan dive from the bridge was his metaphor to help bring closure to the drama he helped stage while acknowledging that Oh Jang-tae's repeated elusion from justice was partly of his doing. In that act, Yoo Jeong-seok believed that he could atone for his sins.
In the final analysis, people act in their own interests. For better or worse. To my mind it's an immutable part of the human condition. Does it make them demons and monsters? It all depends. It depends on whether they've ever learnt to negotiate within the context of family first, then community and then society. When I look at someone like Oh Jang-tae, for instance, it's clear that he never learnt to take responsibility for his own actions. His father cleaned up after him with the family coffer as we heard in the brief conversation with Nam Guk-hyun. All throughout the show we saw this. Oh Jang-tae looked to others to clean up his messes until the bitter end. Everyone had their reason to want to clear Lee Dae-chul's name. I wouldn't say that altruism would be first on the list. Some were motivated by guilt, some by curiosity, some by a need to prove something and others because of camaraderie.
Still Kang Do-chang and Oh Jin-hyuk get their happily-ever-after. True, the system hasn't changed. People haven't changed. Just as Yang Soon-mi and Jin Seo-gyeong predicted. But it's a victory not to be sniffed at. The little people won an almighty battle. One that was born out of blood, sweat, tears and... good o'l fashion teamwork. Clearly the good detective could never have done it alone. Without his cluey maverick partner...Oh Ji-hyuk, without Team 2, without Superintendent Moon, without Jin Seo-gyeo, without Yoon Sang-mi and even Yoon Jeong-seok he wouldn't have made it. There were no superheroes. Just ordinary men and women who did their bit and their jobs. They rose to the call... not always easily nor happily but the important thing is that when push came to shove, they did what was needed.
My sense is that the show realistically accepts the necessity of our institutions: The family, judiciary, police, and the mass media. At times they may seem like necessary evils. Although it is true that our institutions are only as good as the people who inhabit those spaces, they are still pillars of a civilized society. Without them, there is only anarchy in the offing. The ones that always lose out in that deal are the vulnerable. Whatever their flaws, when done right they do serve the purpose for which they are intended.