The show will tell the story of a mysterious red line that appears above people’s heads, connecting them to those they’ve had sexual relations with. Han Ji Uk is a detective who wants to discover the truth about the mysterious red line. Gyu Jin is a quirky high school teacher and Hyun Heup is a high school student who has been able to see the red line since birth.

Park Seong A is a high school student, but, at night, she is a shaman named Fairy Cheon Ji. When she works as a shaman, she covers her face partially to hide her identity. She is famous as Fairy Cheon Ji and she is busy working with her clients who come to ask about their future, fortune, illnesses, and other things. One night, Bae Gyeon U and his mother come to visit Fairy Cheon Ji. Park Seong A has a crush on him at first sight, but she sees that he is destined to die soon. The next day, Bae Gyeon U appears in front of her as a new transfer student in her class. She decides to save him from his destiny.

After Wu Suowei's girlfriend dumps him, he decides to get revenge by seducing her new boyfriend Chi Cheng! It started as a game, but falling in love was never part of the plan.

A senior associate lawyer in his ninth year, An Ju Hyeong seems cold-blooded, but no one can deny his competence in the field. He became a lawyer simply because he found logic and cases interesting, but from the start of his career, he never grasped the idea that lawyers are supposed to protect the weak, uphold justice, and make a difference in the world. Although he's a veteran among associates and has even set a new salary record, he refuses to open his own practice, finding it too troublesome. But now, the once-peaceful walls of his workplace are beginning to crack.On the other hand, Kang Hui Ji, a junior associate at Johwa Law Firm, is a social butterfly who always ends up surrounded by people. She believes that “if you change one person's life, you have changed that person's entire world.” Whether she is lacking or overflowing, she is a confident and honest person.Alongside them are Bae Mun Jeong, Cho Chang Won, and Ha Sang Gi. These five lovable law firm attorneys struggle and grow through various cases, both inside and outside the courtroom, while building solid friendships by having meals together.