I've just finished this Kdrama yesterday and I was totally amazed by it. First of all, all actors were absolutely perfect. Especially Jang hyuk and all actors who've played the victims in this series. You, as a viewer, will feel every single emotion because of how well they acted. Some scenes were a little bit too slow. Most of the time, when the female lead was shown. This was kinda bothersome since her facial expression and how she handled things were somewhat repititive. But apart from that, she did good ! I love how you will see progress with every single episode. It creates a very good image of how everyone has lived and what has happened to them as well as why they behaved like they did. This is a MUST watch for every thriller/krimi/detective fan. The scenes were absolutely crazy!