I just started watching "Unkind Women" and I have a theory about where this story is going, but I don't want to post anything that might ruin the enjoyment for anyone else still watching.
So right now I'm on episode 3 and I had to pause it to type out my thoughts before I can continue to watch and see if I'm right or not. If anyone else is still watching and have their own theories please go ahead and share yours here. Or if you've completed the series feel free to tell me if I'm wrong about something, but please don't completely spoil the ending. Thank you!
Let's start with the grandmother who is a cooking teacher, Kang Soon-Ok. I think Soon-Ok misunderstood the relationship her late husband had with the other woman, Jang Mo-Ran. When Soon-Ok's husband dies and Mo-Ran is pregnant, she assumes the father was her husband and adopts the baby, who grows up to be Kim Hyun-Sook. She does pity Hyun-Sook, but her resentment of her husband's unfaithfulness results in her emotional mistreatment of Hyun-Sook.
Mo-Ran, the daughter of a mistress only loved one man and was engaged to him, but because of her parentage the relationship is broken off. Her older half brother can't reveal their true relationship, but because of his kind love for his sister he causes the misunderstanding with his wife. Mo-Ran is actually the secret sister-in-law of Kang Soon-Ok. Even after her brother dies she uses Soon-Ok's misunderstanding to make sure her child has a safe home to grow up in without the open stigma of being an illegitimate child. The real father is her former fience' Lee Moon-Hak.
Lee Moon-Hak is from a wealthy family and owns a book printing company. He is the brother-in-law to the horrible teacher, Na Hyun-Ae and uncle to the new anchor, Lee Doo-Jin.
Eventually things come out about Kim Hyun-Sook's father, at least among the family, and becomes his heir. This helps her take revenge against her high school home room teacher.
Jung Ma-Ri, at first starts to have a romantic relationship with Lee Doo-Jin, but because of their mothers and eventually finding out they are cousins, the two become more like siblings and good friends. Ma-Ri and the kumdo master fall in love and become the main couple of the drama.
Again, if you've finished the series let me know where I am way off, but don't correct with what really happened.
