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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.

Young-goon, after great consideration, decides to meet Kim Jae-myung after receiving his letter. Jae-myung tells Young-goon to investigate Oh Sang-do, the safe deposit criminal, stating that it will help him with his promotion. Young-goon loses his temper and asks if he called him just to tell him that, but Jae-myung secretly opens his hand and shows it to him.

Oh Sang-do is now in a critical condition. Chi-kwang meets Tae-joo, who was trying to use Sang-do in order to negotiate with the Muil company CEO, in the hospital. Park Si-young infiltrates the intensive care unit in order to get rid of Sang-do for good. Young-goon searches for Kyung-ae, the missing wife of Sang-do.