Kim Ki-duk isn't interested in telling a straight forward story. He repeats scenes (more than once) though the last time normal space-time is fractured. Time (the movie) is more of a metaphor than anything else. A metaphor for what I have yet to decide.
At first I was wondering why the movie wasn't titled Face (since one of the main characters early on decides to have her face changed through plastic surgery); however, it becomes clear that this movie is not interested so much in appearance as it first seems. It is firstly a movie about time.
When we first meet the couple the movie revolves around, Seh-hee (the girlfriend) is suspicious of her boyfriend's commitment to faithfulness. She wonders if he is growing tired of her because they've been together too long. She ultimately decides to try and take their relationship back to the beginning. She wants it to be new in the hope that the newness will hold the relationship together. What she neglects (however trite it sounds) is the invaluability of time spent together. The characters spend much of the movie apart, and the viewer knows that a sad prophecy of loneliness is unfolding.
While the movie can function as a cautionary tale, it isn't really that engaging. Seh-hee is obsessive, insecure, selfish (since she's more interested in being loved than loving), and completely jealous. Ji-woo seems to be inattentive, and unresponsive to her concerns. Clearly there's a backstory of dysfunction that we never see. Throughout the movie, Seh-hee spends so much of the time not listening (and not believing) her boyfriend as well as throwing tantrums that I couldn't sympathize with her. When you can't sympathize with the main character of a story in nearly any way, the story has a problem. I'm not saying a character has to likable to be sympathetic, but I am saying that for tragedy to work correctly (and this is clearly a tragedy) there has to be enough in a character that we wish to see redeemed so that when the character is damned, we feel the appropriate emotional response of catharsis. I didn't feel it after watching Time.
Twice during the movie a character tells Ji-woo that Seh-hee must really love him. Neither character really seems to believe that's true. It's more of a nicety than anything else. We don't believe she loves him either, and that's the problem with this film: she doesn't love him, she just wants to be loved by him. Time can't heal that wound.