I love the 2 leading characters, and the acting was ok. their relationship is as predictable as you could imagine in real life. the second leads stories are just bland. actually, everything is so normal that I just wonder why in the first place somebody needed to shoot that movie, and why somebody could like watching it. if I had to summarize, I would call it "melancholia", and conclude by "what a waste of time!"
there is 1 situation in which watching this could be nice: if you are sad/depressed (whatever the reason), and feel like crying out would help, be my guest!
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a few months later: I didn't know the personal story behind this drama. I am not saying this was made on purpose, but you'll agree that the timing is odd: Song Hye Kyo, the actress playing the main female lead, was divorcing at the time of the shooting. she met her ex-husband (yoo shi jin) on the shooting of "descendant of the sun" (2016). they married the next year and divorced 2 years later (2017-2019). so, when she chose this drama, she was divorcing. I find it very odd that I wasn't able to feel how deeply this must have hurt her.