Seo Do-cheol is a ruthless police detective who delves into the mysterious suicide of a truck driver named Bae. As he investigates, he learns from Bae's son that Jo Tae-oh, the sadistic third-generation heir to the powerful conglomerate Sinjin Group, assaulted Bae for protesting against the conglomerate over unpaid debts. Driven by a personal vendetta, Do-cheol initiates a thorough investigation, provoking Tae-oh's wrath.
In a bid to undermine Do-cheol, Tae-oh leverages his considerable influence to assign him to a different case. He even attempts to bribe Do-cheol's wife with the support of his company's SVP, Choi Dae-woong, but she staunchly refuses. Enraged by the situation, Do-cheol confronts Tae-oh after learning of this betrayal. Seeking justice, he enlists the help of a tenacious reporter to publicize the matter, but his efforts go unrecognized.
Tae-oh, determined to eliminate Do-cheol, hires a logistics contractor named Jeon to carry out his murderous plan. Meanwhile, the internal affairs department interrogates Do-cheol, but his team leader, Oh, timely comes to his rescue. During a harrowing murder attempt orchestrated by Jeon, in which another detective is stabbed, Do-cheol narrowly escapes. Seizing this chance, he and his team gather crucial evidence and earn approval to investigate Tae-oh, but the conglomerate chairman, Jo, ensures that Dae-woong takes the fall for the wrongdoings.
Using his investigative skills, Do-cheol uncovers that Bae was murdered after trying to seek revenge against his assailant, and his death was subsequently staged as a suicide. After questioning Dae-woong, Do-cheol learns that Tae-oh plans to flee to Singapore. In a desperate bid to stop him, Tae-oh throws a lavish party where he encounters his pregnant ex-girlfriend, Jeong Da-hye, and attempts to silence her when she confronts him.
Do-cheol devises a clever plan to set up Tae-oh, framing him for assault against Da-hye. A fierce battle ensues between the police and Tae-oh's bodyguards as they attempt to detain him. Following an intense car chase, a gripping hand-to-hand fight breaks out between Do-cheol and Tae-oh. Despite suffering brutal injuries, Do-cheol ultimately prevails, resulting in Tae-oh's arrest. Both he and Dae-woong are brought to trial at the Supreme Court and sentenced to prison.
In the aftermath of these tumultuous events, Do-cheol recuperates from his injuries in the hospital, determined and ready to return to duty once more.
