Season 1

Ko Tae Rim, a lawyer with a 100-percent win rate, wins another unwinnable case. He is expensive to hire but guarantees the client's acquittal. Seo Jae In, a rookie lawyer who believes justice over money, is struggling to be successful due to the controversy around her. They meet by coincidence and start to run into trouble no one ever expects.

Jae In is desperate to get Tae Rim to work on her friend's case because no one else is willing to. Instead of getting paid for the case, Mr. Gu requests Tae Rim to hire Jae In for the foreseeable future. The case goes well until, Tae Rim meets his mentee, Kang Gi Seok. Due to this loss, he is in a state of confusion.

"Jae In successfully proves her friend's innocence and celebrates her victory. Tae Rim, however, is still underrating Jae In's contribution. Even though she has won her case, she has a moral dilemma. He feels conflicted by the fact her friend may not be innocent.

Jae In wanted to take a case to help a company's employees, but she is turned down for being an inexperienced lawyer. In a turn of events, Tae Rim takes the case for the company instead. Jae In is still angry about the fact, Tae Rim won't help the employees but seek money as his prime objective. But Tae Rim does his absolute best to help his client to fulfill his duty as an attorney.