Mind-blowing drama!
As my headline reads:"Be patient with it for first 2 episodes..." and let me complete, "after that, you won't be able to stop watching it".
The twists will turn your head and so will the plot and it's heart wrenching story.

My heart goes out to such bully victims and frankly this is a kind of drama where the lead was antagonist and still you will sympathize with him instead of his victims.

I don't usually watch serious revenge dramas but this is something that i will strongly recommend.
The acting is superb, be it adults or of the kids... They are amazing!

Just that I feel the ending should have been a bit different given that the last character met with a heroic end.
Not giving in any spoilers I again recommend you'll to watch this so that you'll can recommend this to someone else ;)