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Kim Young-goon, a traffic policeman, chases Son Byung-gil, who ran away after refusing to comply with an inspection during signal violator check-up, and even shoots his gun. Young-goon has to face investigation from the special crime squad, where he meets Doh Chi-kwang, the inspector that came to inspect the case, and lawyer Han Tae-joo, the lawyer who specializes in criminal crimes and who came to defend Byung-gil.

Son Byung-gil argues that he kidnapped Cha-hun because the police have bribed him. He makes a condition where in return of telling where the kid is, he will look for the kid himself which Young-goon, Chi-kwang and Tae-joo accept in order to protect the kid. Chi-kwang gains an opportunity to earn evidence to catch Hae-ryong, whom he was suspicious of. Meanwhile, Young-goon remembers where he saw Tae-joo.

A corruption investigation team is made, and Chi-kwang reports the past cases that need re-investigation to Park Jin-woo deputy director. But the deputy director refuses and tells him to bring a present case. After receiving a call from Hyo-jung, who ran away with the legal fee, Tae-joo realizes that the organ sale case that Chang Hae-ryong is in charge of is related to Hyo-jung's kidney transplant, and takes in charge of the case as he alerts Young-goon.

The corruption investigation team forms a plan to catch Manager Kim and the mastermind, but prosecutor Lee Dong-yoon, after hearing this fact through Hyo-jung, starts the plan on manager Kim first. Young-goon, who was meeting with manager Kim, falls into a crisis and gets injured. Dong-yoon is on a roll as he catches manager Kim's foreign organization, and as the prosecutors and the police agree to end the case, the corruption investigation team does not give up on their investigation.

Kim Jae-myeong requests his son Yeong-goon for a visit for the first time in 15 years and gives him a tip to help him with a promotion. He hands him a ledger relevant to Oh Sang-gon, but angers Yeong-goon.

Sang-do suffers a critical wound and is taken to hospital. Tae-joo notices a thumb with a scar like hers infront of Oh Sang-do's hospital room and goes to verify it. Meanwhile, Yeong-goon searches of Sang do's missing wife.