I think this is my one of most thrilling drama that, I've ever watched. Each episodes give you so much thrill. If you're suspense and thriller genres lover then just go for it without any questions. Very strong characters and story's suspenseful plots are enough to give you thrill on all over your body.
If we talk about of action then this drama haven't that much action but according to the story, the action part is appropriate.
And every character's acting performance was just beyond of my expectations.
I like it very much specially when the music come during the outro. The music was really suitable for this drama.