This drama explores the butterfly wings effect and how changing past choices in one life influences present reality for all of Korea. I've read many of the reviews on this title after I finished watching the show, and I get how some people were disappointed when the theme of the drama switched from fast paced action to more of a political commentary. For me, the change was welcome. I got a little exhausted with the constant "save my dad" segments and was worried the drama wouldn't progress beyond that point. However, they did an excellent job transitioning at pretty much exactly the point where I was completely over them constantly trying to rewrite history to create the best possible outcome for themselves. I liked the moral conflicts of whether what they were doing was right or if they should stop trying and be satisfied with the present state of their world.

The story tackles multiple themes, including political corruption, but also the underlying current of how people change based on circumstance or new information. The suggestion seemed to be that everyone has the potential in them to either be great or corrupt and that no one is immune to the influence of power on their lives. It also really heavily tackles the topic of press freedom and why it's so important to have an independent press system, sheltered from the external influences of the powerful.

The interactions between the two main leads were really well done, made sense, and were filled with chemistry. I felt like they spent a good amount of time developing both characters and I liked that they characters had moments of uncertainty and confusion, where they seemed opposed rather than united. The side characters were pretty well developed as well, and it was interesting to see how different their lives were in each iteration of the timeline. However, toward the end there were for sure moments where I felt like different developing side stories were lost in the fray and not fully resolved.

The actors, in general, did a great job portraying sometimes vastly different versions of their characters in different timelines. The wardrobe and sets were also really well done to add an extra dimension to the timeline differences. The casting was really well done too, the characters you're meant to empathize with you find yourself becoming really attached to, and the villain characters are sufficiently horrible that you feel genuinely pleased whenever they get their just rewards in various timelines.

The ending was weird, I hope there's a second season so I can get some explanations. Initially the alternate timeline calls were linked to the specific phones used, but at the end a different phone comes into play and I want to know the situation that made that possible.

Overall, this drama was worth a watch and I rated it very highly. There were some slow points and a few plot holes that bugged me, so I didn't give it a higher rating. Basically, it was high quality, but not epic. I was satisfied with how the story progressed, in spite of these minor inconsistencies and sometimes dry and bland segments. I wouldn't watch it again because I do not feel like there are additional insights to unpack, but I would for sure watch a season 2, especially since the ending left the story open for one.