Byeon Ho-sung is a hotshot lawyer at a big law firm; with a nearly 100% win rate, his life motto is "Winning is justice, and I am the winner." After Byeon wins a lawsuit for a large conglomerate pharmaceutical company, its chairman Moon Ji-hoon asks him to defend Moon's chauffeur Kim Jeong-hwan, who is suspected to have murdered a female college student named Han Min-jeong. A pool of blood was found at the crime scene where Kim was apprehended, but a body has not been found and there are no witnesses.
Kim insists that he and the victim were dating, but passionate rookie prosecutor Jin Sun-min believes that he was stalking Han. Just when Byeon is close to successfully contradicting Jin's claims and winning the case as he always does, his client abruptly confesses in court on the last day of the trial that he killed Han. Furious at his humiliation and even accused of tampering with evidence, Byeon uncharacteristically embarks on a search for the truth and teams up with Jin. But as he digs deeper, Byeon begins to uncover clues that may link the case back to Moon.
