A reverse comedy that tells the story of a perfectionist assassin who falls and hits his head in a sauna, giving him amnesia. When a down-and-out actor switches locker keys with him, they switch lives until the hit-man, who soon becomes an action hero on TV, starts to remember things.
Saeyoung is a new employee who eventually stands against Leesun, her stubborn team leader. Leesun is upset by Saeyoung's behavior, but she soon learns about ominous stories about Saeyoung. As the stories about Saeyoung are revealed one after another, she becomes a source of fear to Leesun. Saeyoung's stalking-like bullying continues, and Leesun tries to run away from her.
Won-sik is kicked out by her roommate Woo-jung and becomes obsessed with winning her back. She begins to practice pole jumping when Woo-jung proposes that she might change her mind if he shows her something skillful about herself. Young-rok, a former athletic coach makes the incredible recommendation that Won-sik might impress Woo-jung by pole vaulting up to the their roof-top apartment. Meanwhile, idol wannabe and former athlete of Young-rok, joins this crazy adventure at Young-rok's behest, drawn in by Won-sik's determination.
Kwon Yeon-woo is a thirty year old low-level civil servant who works in a district office; quite innocent for his age, he has been on numerous blind dates in an unsuccessful bid to find a wife. After moving into a new place, he begins to encounter a high school girl, Soo-yeong, on his way to work every morning, and she begins to develop feelings for him. Meanwhile, Kang Sook has just started working at the district office straight out of high school, and falls head over heels for older woman Kwon Ha-kyeong.