Cheon Sang-hyuk has been trapped on earth for 500 years and has lived as ‘Cupid’, a matchmaker of humans. Oh Baek-ryeon, an ethereal beauty who committed a great sin in her past life, is doomed to fail every romantic relationship in this lifetime. Just when she is about to give up in love, her fairy Cupid appears in front of her.

Baek-ryeon feels a weird sense of familiarity upon encountering Cheon Sang-hyuk. He secretly watches her wondering why she doesn’t have the red thread of fate unlike the other humans. Meanwhile, the night before the snowstorm, a woman gets kidnapped in a public parking lot in Mt. Inwang, and the witnesses of the incident are found dead one by one.

Baek-ryeon expects Sang-hyuk, who heroically saved her from her stalker, to be the man of her destiny, but he draws the line that he does not want to be in a relationship with a human. Meanwhile, Sang-hyuk and Jae-hee run into each other at Baek-ryeon’s animal hospital. How were they related to each other in their past lives?

500 years ago, Cheon Sang-hyuk, a fairy who had no ties to humans, ignored the warnings of Samsin and fell in love with a human girl. As a punishment, his wings got burnt off and he lost his beloved woman. 500 years later, since he well understands the pain of being alone, he empathizes with Baek-ryeon and eagers to help her out. So he starts by asking her what her ideal type is.

Sang-hyuk begins to suspect that the culprit in the Inwangsan missing girl case and the 1993 missing high school girl case are the same person. Baek-ryeon is upset because Sanghyuk tries to set her up with a random man while she has a crush on none other than Sanghyuk himself. At last, after climbing Mt. Inwang a thousand times, she gets to meet the man of destiny.

Sang-hyuk and Jae-hee learn that Baek-ryeon was a witness to the Inwangsan disappearance incident. In order to protect Baek-ryeon, Sang-hyuk chases down the criminal like her knight in shining armor. Baek-ryeon is happy when Sang-hyuk protects her like Superman and doesn't get hurt even after the intense physical fight, and she gets very curious about his true identity.