Luck-Key

Jae-sung, at rock bottom, contemplates ending his life after a harsh insult from his landlady. He seeks a moment of relief in a public sauna, hoping to wash away the sting of failure. In the sauna, Hyung-wook—an assassin finishing a target—enters, and a chaotic slip of fate occurs when Jae-sung drops soap and Hyung-wook collapses.

Seeing Hyung-wook's ostentatious life, Jae-sung makes an impulsive move: he swaps lockers, steals the other man's car and money, and vanishes into the night. Guilt gnaws at him as the stolen wealth offers a fleeting taste of a second chance. Later, he tries to return everything, only to find Hyung-wook barely conscious in the emergency room.

In the hospital ER, Jae-sung is confronted with Hyung-wook, who grabs him but cannot recall the encounter because his memory is fuzzy. Jae-sung slips away silently, unsettled by what he has done and what he has unleashed. The escape marks the beginning of an uneasy, collided fate between the two.

Hyung-wook cannot pay his hospital bill, and paramedic Lina steps in to cover the costs with a condition that he repay her later. The financial act binds him to a new, unlikely alliance and a debt that will haunt him. This moment becomes a turning point toward a future he hadn’t planned.

With Lina's support, Hyung-wook's hands-on knife skill helps him land the role as the restaurant's main chef, drawing curious customers with precise, practiced technique. The sharp precision in the kitchen mirrors his former life, but in a safer setting. His culinary success marks a surprising new identity taking shape.

Hyung-wook discovers a calendar date and a location that hint at a life he has yet to live: a future as an actor who would appear on a gangster-themed TV show. The clue binds him to a path beyond assassination, even as the life he stole continues to haunt him. The revelation sparks questions about identity and fate.

As the show progresses, Lina's support helps Hyung-wook grow into a more prominent on-screen presence. The on-screen partnership deepens, and a warmth blooms between Hyung-wook and Lina. Their evolving bond complicates the plan to escape their pasts.

Meanwhile, Jae-sung grows suspicious, discovering a secret room in Hyung-wook's apartment and suspecting that Hyung-wook is an undercover cop protecting Eun-joo, a witness who lives in the same building. He begins quietly watching Eun-joo, drawn to her despite the danger of what he might uncover. The mystery around Eun-joo deepens the trio's fragile plans.

One day, Jae-sung answers a phone call for Hyung-wook and meets businessmen pressing about Eun-joo’s survival. He realizes Hyung-wook is not a traditional assassin but someone who helps victims by faking their deaths and sharing the profits. The trio—Hyung-wook, Jae-sung, and Eun-joo—decide to disappear and start anew.

Hyung-wook tells Lina that they cannot be together and leaves to join a larger plan. Lina follows him to the planned fake-death location, where her interference nearly sabotages the arrangement. The fragile plan teeters on a knife-edge as outside forces close in.

The businessmen believe they are dead and walk away, ending their pursuit for now. Hyung-wook and his allies must forge a new life under fresh identities. The immediate danger eases, but the future remains uncertain.

On the TV set, Hyung-wook improvises new lines and confesses his true feelings to Lina, who accepts him. The couple decides to face the future together on screen and in life. In a final twist, Jae-sung and Hyung-wook are poised to star together in a new gangster-themed TV show.