I am just adored by this drama. The suspense, story and plot twist were all done so well. I couldn't easily predict what was going to happen the next episode and just gave up predicting after a while. The story is done so well and I loved that the characters are not top class geniuses like they have prepared their whole life to know what to do in these type of situations. They are normal, everyday human beings that have flaws. Especially In joo, she is like a normal person who got dragged into this mess. It brings a little sense of realism. All the actors did so well in their roles. Especially Kim Go Eun did such a splendid job. The despair and happiness felt so real in the show. The other actors did a spectacular job too. This is must watch, if you like action, thriller and suspense. No boring episodes. It would always leave you at the edge of your seat.