Season 1

Jang Tae-san is a third-rate gangster managing a pawnshop. He is shocked when Seo In-hye, an old flame, reappears in his life after 8 years and wants him to get a blood test. Her daughter, Seo Soo-jin, has leukemia. After receiving news that he is a suitable bone marrow donor, a two-week preparatory window is established for the surgery. Tae-san must remain healthy and virus free or Soo-jin will die.

Im Seung-woo, In-hye, and Soo-jin are delighted by the news of the surgery and don't know what to do. Seung-woo, who holds Soo-jin in his arms and likes her, receives a call informing him of a murder case. Tae-san is taken away by the police as a suspect in the murder of Oh Mi-sook. Tae-san, who is falsely accused, finds this situation frustrating. The vehicle transporting Tae-san collides with an oncoming dump truck, causing an accident.

Tae-san takes advantage of a traffic accident involving the escort vehicle to escape. Upon learning that Tae-san is the culprit who murdered Mi-sook, Park Jae-kyung is shocked to the core, while Seung-woo, who hears about Tae-san's escape, is furious. Meanwhile, while sorting through Mi-sook's belongings, Jae-kyung discovers a clue in Mi-sook's underwear that reveals the whereabouts of a digital camera.

Tae-san jumps down from the mountain like crazy to avoid being caught, but someone catches him. Tae-san disappears in front of their eyes, and Jae-kyung and Seung-woo suspect that someone is behind Tae-san. In-hye hears the news of Tae-san's escape on the news and is taken aback. Meanwhile, Jae-kyung and Seung-woo, who missed Tae-san, start the investigation from the beginning. Seung-woo discovers In-hye's phone number in Tae-san's call history list and is taken aback.

Tae-san runs away after killing Go Man-seok, with Seung-woo chasing after him. Tae-san manages to shake off Seung-woo, only to be met by Kim Seon-saeng (Teacher Kim) waiting for him. Jae-kyung rushes to Tae-san's house upon hearing the news that Tae-san killed Man-seok. As Tae-san enters a village, he hears the sound of a mysterious woman crying there.

Jae-kyung and Seung-woo jump into the water to find the missing Tae-san. In front of the awakened Tae-san, a man with a thick white beard and covered face stands, unrecognizable. Do Sang-hoon learns about the relationship between Tae-san and In-hye, and between In-hye and Seung-woo, and informs Jae-kyung of this fact. Meanwhile, Moon Il-seok visits Soo-jin's hospital.

Jang Tae-san! You are under arrest for suspicion of murder and fleeing the scene! Seung-woo falls into despair watching Soo-jin act recklessly. Upon returning to the office, Seung-woo becomes enraged upon realizing that his team members were deployed for the operation without him. Jae-kyung and the team chase after Tae-san attempting to escape. Meanwhile, Jae-kyung, who has lost consciousness, opens her eyes to find Moon Il-seok standing in front of her.

Tae-san and Jae-kyung engage in a fierce mental battle with Il-seok. Il-seok offers to spare Jae-kyung's life if Tae-san shoots her. Seung-woo is enraged by Jae-kyung's solo actions. Meanwhile, as Jae-kyung enters the prosecutor's office, she unexpectedly comes face to face with Jo Seo-hee who has come looking for her.

Jae-kyung is shocked by Jo Seo-hee's unexpected counterattack. She pushes Jae-kyung down her dead-end path. Seung-woo comes to the district prosecutor’s office. Tae-san decides to meet In-hye at a department store. When Jae-kyung finds out, she deploys police at the department store, and Teacher Kim also observes them from afar. Meanwhile, Tae-san freezes after hearing the conversation between Seung-woo and In-hye.

Il-seok is furious at the news that even Teacher Kim let Tae-san slip away. At that moment, he recalls Soo-jin and smirks slyly. Jae-kyung meets In-hye to persuade her to help with Tae-san's surrender, while Seung-woo goes to find Il-seok. Meanwhile, In-hye goes to see Jang Young-ja, Man-seok's deceased girlfriend.

In-hye throws herself in front of the gun to protect the camera. Seeing this, Seung-woo becomes even more confused. Tae-san and Jae-kyung come face to face in the dark park. Jae-kyung takes Tae-san to her house. Meanwhile, Teacher Kim, who had been hiding and watching Jae-kyung, gets off the motorcycle and shoots Tae-san.

Detective Jae-kyung arrests Teacher Kim who shot Tae-san, but the gun has already disappeared. Mr. Kim is released with a lawyer's identification. Jang Seok-doo and Hwang Dae-joon discover a hidden recorder in the pawnshop and are shocked to hear Tae-san's voice recorded inside. Meanwhile, Detective Jae-kyung arrests Il-seok on suspicion of murdering Oh Mi-sook.

Tae-san discovers Moon Il-seok and tries to escape but is caught by Teacher Kim. Seung-woo, tormented by guilt, confesses everything to In-hye. Meanwhile, Tae-san is surprised to hear Teacher Kim's voice on the phone from In-hye.

While on his way to see In-hye, Taesan remembers Soo-jin and returns to the hospital. He is surprised to see one of Soo-jin's shoes in front of the operating room door. Meanwhile, Han Chi-gook hears a story about Teacher Kim from Tae-san.

Tae-san goes to find Moon Il-seok and Hwang Dae-jun following Jo Se-hee, shaking them one by one. Tae-san is pleased at the thought of being able to clear his name. Meanwhile, someone offers a deal to Moon Il-seok's group, who are at a dead end.

Teacher Kim, who was approaching to kill Tae-san, stops when he sees the person lying on the operating table.