"When a Man Falls in Love" The people whose love is not returned are appearing to be planning a scheme.

In the story line of the MBC drama "When a Man Falls in Love" features two characters who become very possessive when their love is not returned. These two characters are Baek Sung Joo (Chae Jung Ahn) and Koo Yong Gap (Lee Chang Hoon).

Baek Sung Joo is completely in love with Han Tae Sang (Song Seung Hun) but he does not think of her as a woman. To Han Tae Sang, Baek Sung Joo is only a business partner who will not leave his side. When Baek Sung Jooo finds out about the relationship between Han Tae Sang and Seo Mi Do (Shin Se Kyung), she becomes more possessive.

Baek Sung Joo buys herself a ring that looks exactly like the ring Han Tae Sang bought for Seo Mi Do. Then, while Han Tae Sang is speaking to Seo Mi Do on the phone, Baek Sung Joo yells out, "Darling!" When Seo Mi Do expresses her discomfort regarding Baek Sung Joo, Han Tae Sang tells Baek Sung Joo, "Let's not ever meet again."

However, Baek Sung Joo says, "You're going to regret this for sure... for not recognizing a woman like me" and begins to cry.

Meanwhile, Koo Yong Gap begins to get possessive with his love towards Baek Sung Joo. Koo Yong Gap attempts all types of evil doings to win over her love. When he finds out that Baek Sung Joo has been secretly meeting Han Tae Sang's biological mother, Koo Yong Gap thinks about how to take advantage of this information. Koo Yong Gap eventually goes to see Han Tae Sang's mother personally.

It appears as though Koo Yong Gap and Baek Sung Joo will be working together. Koo Yong Gap even tracks down the man that Han Tae Sang's mother had an affair with. It is hard to predict what Koo Yong Gap and Baek Sung Joo will do to get revenge on Han Tae Sang. In the meantime, Baek Sung Joo has already come to the decision to send Seo Mi Do and Lee Jae Hee (Yeon Woo Jin) on a business trip together. When Han Tae Sang decides to join this business trip, if is unclear how many twists and turns this story will take.