This was actually recommended to me the year after it was release and due to the fact that I'm also an avid fan of tv series having crime solving themes. I recently just watch it and finished it today.

At first, I did not expect anything from this thriller, although, I already find it interesting. The fact that I finished this in one-sitting just show how good it is. Plot twist within a plot twist - which is the reason why it will leave you hanging and wanting for more.
Just like OCN drama in a nutshell, every episode is filled with crime, suspense, action-pack, mindfuck and heartbreaking scenes. Only a little time to relax and unwind. This might be the reason why, after watching this, I'm emotionally unstable, I feel relieved and at the same time depressed. The scenes always ingraining on my mind. The others are right, this drama will really get to you.

The cast, indeed, portray their characters well. I was attached, badly. The main detective is headstrong that is both his weakness and strength, but if I was also in his position, considering what happened to his daughter, I would be like that too. The prosecutor is greedy but she subtly cares, straightforward and pragmatic. The reporter is stubborn which is also her weakness and strength. And the clones, oh the clones, the first one carries humane tendencies, warm, while the other is cold, neurotic and slowly losing it. One thing these clones/twins have in common they are both fragile mentally and...physically.

The music production was perfect. Every sound emphasizes/heighten the feelings, the actions, the expressions and the dialogues of each scenarios. The 1st Ost "Nightmare" by Mad Soul Child is the absolute combination for the drama, or specifically, other says that, it is a song suitable for the evil twin.

All in all, this is really indeed, one of those dramas that I will watch again because it really impacted me, strongly.

Btw, this show has led me to be curious about stem cell and how cloning human is indeed unethical and blasphemous.