I enjoyed watching this drama. Above anything else, it's about sticking to your values and yout own self. Friendship and loyalty. Which is good, and interesting to watch. Specially when you see the characters influencing each other's actions. Even though the male lead is presenting as this upstanding guy with amazing morals, there are times in which he moves things according to his endgoal, even if he knows deep down that it's probably hurting somebody (like how he kept coming back to the ex-cop or in a way took advantadge of a character's feelings for him to keep her by his side when she could've have better offers). And the opposite thing applies, one of the characters is cynical and more of in a gray area but learns from watching him and I like that they start to enjoy live and human interactions together. She says it in the final chapter, neither of them knew what human warmth was until they tried to built it together.
I liked that the drama talked about racism, transphobia, ageism and so on, but I find it was a little shallow on its approach. Things don't solve themselves by miracle and knowing how the world, specially Corea, is about those topics, I don't really believe for example in the scene in which a character can easily say she is trans and everybody cheers on her. It's difficult to find that scene realistic, but I want to believe that there'll be a time in which it won't matter. Like the show said, you don't have to prove yourself, your choices, and in my opinion you don't owe people an explanation. I also don't like how easily forgiven the character who outed her was. Like I wouldn't even do that to somebody I considered my enemy, even less to a friend and in a society like that, wtf.
Other issue I had is that I do like the endgame couple and I was sold in why they fell for each other. He broaded her worldview and made her want to live and have values to believe in and work to achieve them by watching him and then later on wanting to fight for him. And she was his pillar, he's always done everything by himself, putting barriers even among his friends, but little by little she became a part of himself without his notice. I understand that, so that's why I liked the pairing. I just would've liked more scenes of them in the 2020 timeline pre-kidnapping in which he catches himself having feelings for her he can't quite understand yet. I think the writers clun to the love square-sometimes pentagon for way longer than they should've have done so.
I wouldn't say this is the best drama I've ever watched, but it was worth watching and I'm glad they're starting to include social issues like the ones they did. I also understand that there might be limits as far of what the writers can say on tv, and that even having a trans character and a character with a darker skin tone it's already a step forward.