Let me make it clear that I am NOT your average kdrama viewer for the following reasons:

1. I FAST FORWARD A LOT because I have little patience for scene fillers where 20+ seconds is spent with the actor(s) gazing wistfully at the distance. I need action to happen FAST...
2. I am always looking for MATURE, STRONG LEADS especially where the female leads are concerned... and
3. I do not watch what everyone else is watching simply because I think I'm looking for different stories: MORE SUBSTANCE, LESS CRINGE. (I really disliked Her Private Life, couldn't stand the FL in Something in the Rain, and for that reason, I will never watch CLOY), and lastly,
4. I think that kdramas take too long to begin and then rush to end -- I mean, hello, what the hell kind of ending was that in Cheese in the Trap??!

Having said that, if you are similar to me, and you like watching kdramas with romance AND suspense, then
WATCH THIS DRAMA NOW.
It's a 16-episode NOT 32 episode story that is solidly written and executed. Enough time is given to the flashbacks and present day so I never felt confused. The actors are so well-cast, they transform into the characters , so much so that I found myself getting more and more invested in them as the story went on. Aside from the ML being exceptional, Heo Joon Ho nailed it as the psychopath; every scene he was in crackled with electricity, as did his accomplice, played by Hong Seung Bum. The FL was strong and compassionate, certainly someone I could root for.

The pace of the story is terrific, and the ending is tied up neatly. I am a chronic kdrama-dropper, but not with this story. I hope i could find more stories like this one.