I haven't finish Jang Hyuk or Soo Ae's works before. I came by chance & decided to watch it. I was blown away with this movie. The acting was top-notch especially Park Min Ha. She may be a child actress but she brought her character to life. Story: It's a disaster movie, not original. But the flu was an original concept. Acting: As I said above. Park Min Ha blew me away. I love the father daughter chemistry between Park Min Ha & Jang Hyuk. There was some romantic chemistry between Soo Ae & Jang Hyuk even though there was never a romantic plot. I like it that the romance was never the main theme of disaster movies or dramas. I cried so many times in this movie & for a long period of time. One scene with Park Min Ha crying made me cry so hard(watch the movie to find out) that I had to look away from the screen & took a break for a moment to recompose myself. Music: The music fitted the right moments. I want to look into the ost. But it was mostly instrumental music(or all because I watched this 2 months ago). Rewatch: It's low because I don't want to cry for too long again. Some things were too painful to watch. I would recommend it. Watch it once, but don't watch it again or once a year. Why watch: for the actors & actresses. If you like medical, disaster & action type movies then you'll probably like this one.