If a romantic drama series is going to conclude with an unresolved ending that leaves it up to the viewer to decide whether the couple end up together or not, then the journey toward that ending has to be sufficiently rewarding. I don't think that it is in this case.
The series is very well acted, and has a good ensemble cast, however i found the scriptwriting very disappointing.
This series would have us believe that nearly every Korean lives with their head in the sand, and is unable to carry on a frank conversation, even when they are in private.
I found the main relationship to be unrealistic, with the primary couple failing at every opportunity to behave in a normal human manner.
They appear to prefer talking in riddles, than hashing out their situation like regular people would.
In fact the only main character that seemed to behave in a rational manner was So Kyung Pil, who was too often portrayed as the villain for only being honest to himself and others.
When i compare the writing here to two of my favourite Korean romantic dramas - One Spring Night (Bombam), and Something In The Rain - i find that it pales in comparison.
It is at least better than My Liberation Diary, which meandered along and went nowhere, but not by much.
Despite my frustration with the actions and decisions of the characters, I watched it all the way through in the hope that I would at least be rewarded with a satisfactory ending. Alas i was again disappointed. It is possible to conclude a romantic story successfully with an open ending - watch My Mister for a prime example - however The Interest Of Love fails in that department too, due to the inferior writing.
In the end I felt that my time could have been better invested elsewhere, and am still craving to find another Korean romantic drama of the standard of the aforementioned three series.
