Are you a fan of serious time travel thrillers? This drama might not be for you.

So I'm a fan of time travel/alternate worlds dramas. Fighting against fate, trying to save someone from death in the future. Tampering with past events to try to achieve better results, but often ending up getting unexpected, unwanted changes (the so called butterfly effect). My two absolute favorite kdramas that embody a lot of these elements are Signal & Nine Time Travels, but I also enjoyed Train, Times, or anime like Steins Gate, Erased, Higurashi.
I never watch dramas that are on the lighter side: comedies, romances - things like these I only tolerate in small amounts, when they are just a (rare enough) addition to the serious, character & story driven show.

This is a review-warning for people with similar tastes to mine.

The first episode already made me highly skeptical of whether Some day or one day is for me - but we all know there are tv dramas that take time to pick up but end up being worth it, and this show has to have the score of 9 for a reason. So I tried getting some non-spoiler information if I should stick with it. The opinions were prevalently in favor. To quote a few:
- "One of my all time favorites. I dropped it multiple times though and like everyone says, it shifts just about where you are right (ep. 2) now to be good."
- "I understand your dilemma as the first two episodes are foundational (and a bit slow) to creating such a masterpiece. "
- "You do need to get through the first few episodes, because they are tonally very different from the rest of the show"
- "The first 2 eps were bad imo, but it definitely does get better. It gets so much better that I completely forgot those first 2 episodes. "
- "When the time travel happens and the main group start interacting— that’s probably when you’ll be hooked"
- "Story telling starts slow. Was kinda bored for the first 4 episodes before it started to pick up"
- "Romance is not the main focus of the show"

Keeping the opinions I've read in mind, I continued watching and passing the checkpoints: 2 episodes, 4 episodes, "second half". And with every episode I continued convincing myself "it's going to get better now, the mood of the show is about to shift and I'll finally get what I came here for".
I never had to fast forward any parts of the shows before, likely because I successfully avoided everything that - given my described tastes - I'm not the target audience of. But this time I've caught myself doing this several times. There's so many slice-of-life conversations between the 3 main characters, so many flashbacks to ML & FL romantic, "sweet" moments, so many gag-like situations that I simply don't find interesting at all. Being as far as 6 episodes in, I was fairly confident this wasn't going to be the kind of time-travel show that I thought it would be, and that "Thriller" in the tags is likely a mistake.

'Some day or one day', despite a couple of events with short screen time in the first half that were purposely left to be explored later, only began to scratch the surface of what a person like me seeks in the shows towards its end: from episode 10 and on. And I'll be honest: this part was great. The climax of the drama will definitely stay in my memory, it wasn't just interesting - it was moving, it evoked the kind of emotions that I craved for. And while I'm on the good things, I must also mention music. I'm absolutely in love with some of the melancholic piano soundtracks: at least 3 of them are going to make it to my favorites and they will most certainly help me carry only the good memories with me on my way out. Perhaps this is already happening - as I'm writing this review and listening to the OST, a part of me begins to miss 'Some day or one day'. But emotions aside, I'm convinced that someone, who decides to pick this show and:
- is not into slice-of-life teenage romance
- prefers sad, touching stories over cheerful conversations
- expects to see a lot of time travel and observe the changes to the world they bring

will have to treat the first 9 episodes as a long buildup - and that raises the following question: Is it really worth it? Perhaps it's better to leave this show to the audience with different genre preferences that will appreciate every bit of it, not just the finale (rather than end up grumbling "just because it's not what we want it to be" ... ;-)).

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