I'm going to be honest here and very clear: this drama annoyed the pants off me! I love Kdramas, but I am finding again and again the same cliches dressed up as new, but in fact they are fundamentally unoriginal. It's a shame because other excellent qualities in the performances and production can be so deeply undermined.
The good points : excellent ensemble acting from all the cast; creation of a believable small community, imperfect, but perhaps unusually accepting and supportive; some believable character development for several individuals (though this is not consistent); creation of some complex characters where motives as well as thought processes are not transparent.
Irritations : the plot relies too much on flashbacks to reveal events instead of the discovery of evidence that can be used in court; flashbacks are used too liberally to manipulate the viewer and artificially create suspense - in fact they are the main medium for suspense as I recall it; the plot is made unnecessarily complex by revealing information out of sequence for no reason; some individuals at times respond in ways completely psychologically wrong for their character, even though they are under severe stress - I could not believe these would react in these ways, and these reactions seemed to me to be present only for effect; creation of suspense in the drama was also too dependent on heavy handed music; yet again we find every character with any substantial level of money, influence or power is entirely corrupt. This should not really count as a "spoiler" because it seems to be normal n Korean society, but I am tired of this cliche.
Would it be SO HARD to write a drama where the people who actually could help are in fact competent and HELPFUL? or at the very least well-meaning or even benign? Could we not see a drama where the villains are, in fact, villains? Why is it that only corruption is supposed to be interesting or believable? - it quickly becomes boring. Ordinary people are, I believe, far more interesting than these people who from the very start we can feel are deeply questionable: and professional villains, acting in their alternative society, can indeed be just as difficult to convict - more believable and thus more interesting than these tropes.
Come on Korea - give us some different flavours instead of the same old spicing. You are doing a disservice to your actors and directors.