When doubts arise about a five-year-old murder conviction, a veteran detective partners with a young hotshot to hunt down the case's hidden truths.

One day, during a university festival where people are often known to find a partner, the 3 incredibly single members of the robot club decide to attend. There the sloppy and timid Hwi-so meets a very aggressive girl by the name of Hye-jin. His romantic advances, which he learned through reading books and watching YouTube, finally wake up to make their move. But will two finally become one this fall?

As a chief of staff in the National Assembly, Jang Tae-jun influences power behind the scenes while pursuing his own ambitions to rise to the top.

Drama tells the story of Ko Dong-Man and Choi Ae-Ra. In their school days, Ko Dong-Man took part in taekwondo. Now, he makes a living by working as a contract employee and also goes after the UFC title. Choi Ae-Ra hoped to become an announcer, but she gave up her dream. Now, she works at the information desk of a department store.

Park Cha O Reum works as a rookie judge. She is in her mid-20's and follows "an eye for an eye" principle. She does not accept prejudice or blindly follow authority. Dealing with cases, she and her colleagues, including Im Ba-Reun, grow as persons.

Chun Jae In is an elite detective with a genius IQ, who guided by only facts, logic, and numbers. Meanwhile, Kim Dan is a rookie detective who can see ghosts. They work together to uncover a conspiracy involving a powerful organization.

The memory of their painful breakup still fresh in their minds, two former lovers reunite years later as a top actor and a documentary producer.