Baek Hee-sung (Lee Joon-gi) is a skilled jewellery maker, dedicated father and loving husband. He also might be a murderer, a secret he is desperate to keep from his wife Cha Ji-won (Moon Chae-won), a detective. As his wife begins investigating a series of unexplained murders, the fragile illusion of a perfect life begins to crack. She begins to suspect, and secretly investigate Hee-sung, who is desperately trying to stay one step ahead and keep the life he has built afloat.

**SPOILERS AHEAD**

I liked this, despite its flaws, and I think about it so often it surprises me.
I recommend it cautiously for those who like thrillers, even if it's not that unique on that front. My major issue with it was that the audience had most, if not all, of the pieces of the puzzle from the beginning. We were privy to all of Hee-sung’s decisions and schemes- meaning we had to spend a lot of time in the beginning watching as the Ji-won floundered around making frustrating accusations and mistakes. [spoiler] This show did have me guessing whether or not Hee-sung actually was a serial killer on multiple points, but I wonder if the cat-and-mouse element would have been even more enhanced if we had been given even less information on Hee-sung’s decisions. We will never know. [/spoiler]

The real selling point of this show, for me, is the romance part. Our murderer-and-detective couple’s solid relationship was the backbone of the series. Great chemistry. So natural and intense, mature and believable. It was palpable.

[spoiler]The series really found its strength in Hee-sung’s ability to have convinced himself he is truly incapable of loving anything. That was the foundation on which he based all of his interactions - that he was faking everything. As a viewer, from the beginning, you could tell that was simply not the case. He was never shown how to display socially acceptable displays of affection/love, and he had to learn how to mimic them from other people. That does not mean he did not feel it, and he truly believed himself a monster undeserving of any form of life. The moment he is given the opportunity to throw away Do Hyun-so and every shred of that life, he takes it without a second thought. He becomes ever more desperate to hold onto this new life when he meets Cha Ji-won - all of his decisions through the show are to hold onto Ji-won, even if he doesn’t realise why he is behaving this way. That man truly loved his wife, and vice versa, and I would throw myself off a bridge for them to be happy and succeed. [/spoiler]