In the year 2013, the narrative of Villains takes us on a thrilling ride with Han Su-hyun and J. As Su-hyun makes a delivery of counterfeit notes, her encounter with a currency counter sets the stage for a nail-biting sequence. Unaware of the police lurking nearby, their ears pressed to the walls, a woman at the counter saves the day by tipping Su-hyun off. A chase ensues through the streets, with J springing into action to help Su-hyun escape.
It turns out that J has been stalking Su-hyun for two weeks after hearing whispers about her counterfeit bills. Her initial discomfiture gives way to intrigue as she learns that he needs her for a heist. J's proposal is tempting: 300,000 fake $100 bills to swap for real money, totaling approximately 30 billion won. The funds would be split evenly between them. Su-hyun, exhilarated by the opportunity, presents the idea to her master, Yang Dosa.
Although initially skeptical, Dosa is captivated by J's master plan. Over the next three years, they collaborate seamlessly, executing a heist of epic proportions. J, the mastermind behind it all, hatches a scheme to rob a casino by laundering the counterfeit bills into real money. The team includes a North Korean defector specializing in super-note printing, Kkangsuni, and Yang Dosa, a master banknote artist and Su-hyun's sole successor.
Between 2013 and 2016, Su-hyun works undercover at a casino counter, swapping fakes for real money with ease. The heist brings her immense satisfaction, and she even contemplates becoming a crime architect herself. Yet amidst her feelings for J, he warns her against trusting a con artist. He reminds her that their life is a facade, where betrayal is the only honesty they know.
J's plan to vanish entangles Su-hyun, imploring her to join him in his escape. However, she chooses loyalty to her foster family, Yang Dosa and her sister, Yang-yeon. On the way home, a call from Dosa interrupts her solitude, informing her of a police officer's demand for a ransom exchange in exchange for their freedom. Su-hyun, mistrustful of a trap, hurls towards home, only to collide with the Chief of the Narcotics Unit at Incheon Jung-gu police station, Jang Jung-hyuk, and his team, who are departing with a truck laden with cash from their residence. Unfortunately, the encounter is met with amnesia as Su-hyun doesn't recognize them. Her pursuit is cut short by an explosive detonation that engulfs their home along with all incriminating evidence. Stunned and unconscious, when she regains consciousness, Su-hyun rushes back to the inferno.
Su-hyun extracts Yang-yeon from the burning remnants and desperately searches for Dosa. As she stumbles upon J emerging from the basement, clad in a gas mask, she discovers Dosa's lifeless body within. The tragedy devastates Su-hyun. Emerging from the flames, Cha Gi-tae, the head of the NIS financial crime unit, arrests her as J drives away into the night. Under questioning, Su-hyun confesses their three-year endeavor, blaming J for Dosa's demise. She believes he betrayed them, murdered Dosa, and absconded with all the money, unaware that Jung-hyuk and his team had stolen the cash.
The episode concludes with a fast-forward to 2021, where J's hand is seen striking down a man's life and placing a $100 bill in his mouth.
