I mean if he cooks, cleans, cherishes you and your child, takes care of the house, creates beautiful metal works of art, and looks like Lee Joon Gi, does it really matter if he is *allegedly* murdering someone in your basement?! I mean no marriage is perfect!!!!Right?!
Jokes aside, this show was one of my favorite shows that I watched this year. I didn't so much as watch it as I inhaled the show!

Let's get to it!

You should watch this show if you like:
1.Mystery stories
2.Detective stories that develop in a non-traditional manner (not a police procedural standard plot)
3.Established relationships
4.Handsome husbands who do the domestic works while their wife kicks ass
5."Sometimes I look at my spouse and wonder if they ever murdered someone..."
6.Psychological thrillers
7.ROMANCE THAT CUTS YOUR HEART OUT AND LAUGHS AT YOU AS YOU BLEED ON THE FLOOR
8.Happy endings that really put you through the wringer for it!
9.Cliffhangers
10.Childhood Trauma
11.You know this east Asia trend of watching hot men suffer and cry A LOT? It has that! (I love it!)

This show starts with a happily married couple, Baek Hee Sung and Cha Ji Won, and their little daughter. Everything seems great about their marriage. Ji Woon is a detective and the show starts when she gets assigned to a case of domestic violence. She believes in the sanctity of family (since hers is so perfect) but this journalist she knows tells her about this really terrifying serial killing case from almost 20 years before, and how families can cover some messed up secrets. Then she ends up exhuming that very same case when a copycat shows up. Soon, she keeps getting vibes that her perfect (truly perfect) husband might be involved in this gruesome serial killing case from the past, in a very sinister way and everything starts to fall apart.

This show has an amazing plot! Everything moves so seamlessly and the plots connect so well. There is not much time wasted on pointless B plots and what it does have in that regard is connected to the main story in a way that moves the story forward while still being compelling separately. It does wrap everything up in the end with a neat little bow but I personally liked it. Some people prefer dangling unrelated B plots that just waste time and lead nowhere and mean nothing to the main plot, maybe, but I preferred the way the show did it. It's such a thrilling plot too, I mean I was on the edge of my seat the whole time. Now I didn't totally get hung up on the "Is he? Is he not?" suspense of the show because I just liked the character immediately. Halo effect activated (or was already activated, I won't get into it because SPOILERS!) and I was just rooting for the story to move forward instead.
The romance is very good in this story too. I usually prefer detective shows without family drama but this show managed to change my mind by intertwining love, family, and trauma so perfectly together with the murder, mystery, thriller side that I was in love with where it was going with it. Every episode has some kind of tie-in from the romance into the events and the couple is so endearing that it just melts your heart. The supporting couple duo was also well-done. I really liked how that relationship developed so realistically. It was very mature and self-aware and not just there to be cute which I really appreciated. I know some didn't like the happy ending because it seemed like fan-service. I have my own theories on why it wasn't fanservice and why it mattered that it ended like it did but that will be spoilery so I won't write it here.
There are essentially two timelines in the show which slowly come together. I really liked how we got a drip of information from the past, it made everything that much more interesting.

The acting in this show was PHENOMENAL! Even then the 3-year-old baby was good! Lee Joon Gi was perfect obviously. He just acts so hard it's like a punch in your gut, right? Anyway, Moon Chae Won was amazing too. She did this thing with her voice when she got emotional that was just perfect. Their chemistry was perfect too. I think they are my favorite pairing from the 2020 shows that I have watched. They really sell the "we are already married" dynamic and they are both good in both the emotional scenes and action ones. Jang Hee Jin's performance was subtle, Nam Ki Ae and Son Jong Hak were terrifying. Kim Ji Hoon was...a bit too much for me. I felt like it was a bit too melodramatic next to the other actors and it amped up the whole show's melodrama level because then Lee Joon Gi became too melodramatic and ... I get why it was like that but...didn't love it! The detective trio was great. Their comradery was so organic and endearing. And the baby was also great! So cute.

Cinematography, lighting, and set-design was aesthetically homogenous. They all looked like they belonged to the right show. They were all well-matched for the psychological thriller set up and helped amp up the tension and atmosphere.
The music was ok. -_- I don't know. It was music!
Negatives: Some would complain about "coincidences" in the story but let me just get that out of the way. There are really only two coincidences in the story (the rest are just, at least to me, natural consequences of the situation the story has laid out) and I wouldn't call them that either. I would say they were rhetorics of the story. These two coincidences are not really there for the convenience of the plot but there to actually set up the plot. What I mean is that each story starts with some given facts. The "what if X happened/what if Y did this and then... the plot starts". So basically in order to tell a story, you have to create a situation that you will put the characters into and then see how they react in those circumstances. That's what this show does on several fronts.
What if a detective is married to a high-functioning sociopath who has been tricking her, their whole life?
What if two characters' fates are forever entangled because of a mutual acquaintance?
What if your past comes back to haunt you?
What if you get a chance to solve the mystery that has been haunting your adult life?
These are all the situations that the plot wants to address. If we say "well, it's too coincidental for a policewoman to meet a psychopath" then maybe you shouldn't watch this show because that's literally what this story wants to explore. There are tons of shows where the detective is married to a fridged-spouse or a teacher or something. You can watch those if you hate this plot! lol. So yeah...not a valid complaint. Especially when you consider the fact that every single Kdrama has ridiculous coincidences right and left. Everyone knows everyone since childhood. All ten Korean characters who make the main cast have all met each other in a foreign country at the same time! Everybody is related... that's just how they are. Just turn off your coincidence-meter when you watch Kdramas!
Now I'm not saying there weren't any plotholes or that situations weren't conveniently solved BUT overall, the show was enjoyable enough that it didn't matter. The point is to have a good time watching a show and this delivered and it was above average. WAY above average.
Also, just asking viewers, if they'll forgive a murderer husband in favor of him cooking, is such a profound question. I have been thinking about it for weeks and I still can't come up with a genuinely moral answer to the question!!!! I mean he's super handsome too! He's not just a good cook and a perfect dad!