A good revenge movie , i really liked the third act it's so unpredictable and surprising that she killed her i really thought she was just hallucinating and thinking about it but, when I saw the body i was shocked , i didn't like the beginning of the movie, and I really hated the student, but i think the role is meant to be like this, innocent from the outside but really dark and evil from the inside, i liked the role of kim ha-neul although she was stupid, but what she did in the ending out of rage was unpredictable, but she was holding the anger all the way from the start of the movie, I'm used to watch genre movies and awards contenders like this so it was good to watch this,it feels like the director really wanted to make a kind of an american oscar contender, for me it's an 8 out of 10