Watch this movie because of the news of the remake movie "Similar". I think this movie is not that bad as some said. Yes the ending is not good or not normal like other lovey dovey living in dreamland kind of love story. And the story is a bit flat, no really excitement / mystery / action / love, it just a flat daily life story of a college girl (except of the strange connection to the future time). But don't most of of us also most of the days living this monotonous flat daily life?
This is the time when Kim Ha Neul and Ha Ji Won still very young and quite new in the industry.

Acting
Acting wise both can deliver the emotion and expression well. The male lead in the other hand, the acting is a bit off to me, he looks like an autism or a bit of dumb? The expression is a bit strange too.

Story
The story is quite refreshing to connect with the past and future (but in real life this likely to happen though). The main focus is not the love story, but the daily life of a normal college student who have a crush to her senior. She's shy in nature and not the type will pursue a guy even how she like him. It just it's not so clear how actually the guy feelings toward her, does he like her? If yes he should have pursue her and not go out with the best friend.
Fate bring connect her with the future son, even without any words they recognize each other: people leave their scent and some pass down to other people. So the father pass down his scent to his son and so she can recognize him even she never met him.
But the thing is why must them connect with each other? Usually this kind of genre will have some unresolved things that need to be resolve, but for this story there's no really anything to resolve or change, it just a story telling and nothing more to it.

Overall the story is not the best out there, but also not that bad. Still watchable but don't expect a love story or action or thriller or mystery. It just a normal daily life story with some unrealistic present / past / future connection. Don't expect too much.