“To win is the law” - Yoo Jiyeon, the Lawyer
Jiyeon is the best lawyer in town with her perfect winning streak. Winning, rather than searching for the truth, was her goal but she is forced to take on the worst case ever: “Exchanging a murderer for her kidnapped daughter in just 7 days.” Proving a murder innocent is no hindrance to her ethics as a lawyer. Already, her daughter’s life is the justice in the world. In order to get her little girl back, she must prove that the convicted murderer is innocent.
 
“A corrupt cop is a cop nonetheless” – Kim Seongyeol, the Cop
Seongyeol is under internal investigation, and his neck is on the line. He is always hassling Jiyeon to help him out whenever he is in a deep hole, but he understands and cares for Jiyeon and her daughter Eunyoung. After learning that Eunyoung has been kidnapped, Seongyeol devotes himself onto the case. His persistent and tenacious investigation brings out the true cop in him.
 
“Show me justice in this world”- Han Sookhui, the Mother of the victim
For Han Sookhui, the world turns dark whenever she thinks about the daughter she has lost to the ruthless murderer Jeong Cheoljin. But she is shocked to learn that Yoo Jiyeon, who has never lost a case, is defending the murderer of her daughter. Han Sookhui feels as if her daughter is killed again. It is unthinkable to let a killer like Jeong Cheoljin walk free. The only thing she can rely on now is the belief that “justice always wins in the end.”
 
“This is why it’s worth living” – Jeong Cheoljin, the Murderer
Jeong Cheoljin is serving his time in jail, waiting for his death sentence. Even though he is appealing, the circumstances and evidences all point to him as the killer, so to be proven innocent is almost impossible. One day, a beautiful woman comes to see him: Yoo Jiyeon, the best lawyer in town. She declares that she will defend him in the appeal, and already sure of victory, he begins to look forward to his release.
 
“I owe you a big one” – Yang Changgu, the Thug
Yang Changgu is a thug who was acquitted thanks to Jiyeon. He still remembers the day when Jiyeon, as they were leaving the courthouse victorious, hands him a vital evidence against him and says, “Put this in your closet for 15 years – let it serve time instead of you.” They run into each other again when Jiyeon takes on the Jeong Cheoljin case. How will their second meeting end?
“I won’t lost time time”- Choi, the Prosecutor
Prosecutor Choi is Jiyeon’s law school alumnus, but always loses against her. When Yang Changgu is acquitted, his pride hits rock bottom. His next case is Jeong Cheoljin’s appeal, and his chance to redeem himself against Jiyeon. He is already confident that he can win this time.
 
“You will never see your daughter again” - K, the Kidnapper
One day, Jiyeon receives a call. “You will never see your daughter again.” K controls the whole situation through his phone. His face and voice is unknown, but he knows Jiyeon’s every move as if he is standing right next to her. Who is he? Is he someone close to her? Why had Jiyeon become his target? When his identity comes to light, the case begins to solve itself.