Fact1: Jae-sung finds does not remember anything due to concussion, Fact2: Hyung-wook is Jae-sung because of locker key, Fact3: Lina finds him job at mom 's small restaurant, Fact4: that actor is supposed to appear in gangster-themed TV show as extra, Fact5: Jae-sung watches over her and over falls in love time
Output: Jaesung, an aspiring actor who has hit rock bottom, prepares to commit a suicide. After his landlady insults him, he first cleans himself first at a public sauna. Hyungwook, a notorious assassin, cleans himself at the same sauna after killing a target. Hyungwook slips on a soap Jaesung accidentally drops and passes out. Remembering Hyungwooks luxurious look, Jaesung switches his locker key with Hyungwooks and steals his car and money. Feeling guilty, Jaesung later tries to return everything to Hyungwook, who is recuperating in the emergency room. When Jaesung finds that Hyungwook does not remember anything due to a concussion, he leaves without telling Hyungwook anything. While Jaesung enjoys Hyungwooks money and fancy apartment, Hyungwook struggles to remember his identity, assuming he is Jaesung because of the locker key. Hyungwook can not pay his hospital bill, so Lina, a paramedic, pays it for him after he promises to pay her back. When Hyungwook realizes he is bankrupt, Lina finds him a job at her moms small restaurant. With his amazing knife skills, Hyungwook becomes the main chef, drawing many customers for the restaurant. He later finds a marked date on a calendar with a location and learns that he Jaesung in reality is an actor who is supposed to appear in a gangsterthemed TV show as an extra. Though he initially struggles as an actor, Hyungwook excels in action scenes thanks to his real life skills. His role in the show becomes more significant with Linas help as the show progresses. Hyungwook and Lina also find themselves liking each other. Meantime in Hyungwooks apartment, Jaesung discovers a secret room and thinks that Hyungwook is an undercover cop protecting a witness named Eunjoo, who lives in the same building. Jaesung watches over her and, over time, falls in love with her. One day, Jaesung answers a phone call to Hyungwook and meets with businessmen who ask him why Eunjoo is still alive. Jaesung realizes that Hyungwook is actually an assassin hired to kill Eunjoo. After a picnic with Linas family, Hyungwook recovers his memory and finds Jaesung and Eunjoo in his own apartment. Hyungwook reveals to Jaesung that he is not a real assassin and that he has been trying to give a new life to assassination victims by faking their death and sharing the money he makes. Hyungwook, Jaesung, and Eunjoo devise a new plan for themselves so that they can start a new clean life. Hyungwook tells Lina that they cannot be together and leaves. Heartbroken, Lina follows him to a place where Hyungwook, Jaesung, and Eunjoo are trying to fake their own deaths in front of the people who hired Hyungwook. Linas unexpected interference almost ruins the plan. The businessmen believe that they are all dead and leave. Later, Hyungwook tells Lina who he really is and apologizes. Lina, not sure what to do, takes him to the set of the TV show to finish the final scene. On the set, Hyungwook improvises new lines and confesses his feelings to Lina, who accepts him. Jaesung and Hyungwook later star together in a new TV show.