The story tells about the protagonist Park Yun-gang, who was the last swordsman of Joseon during the Kaihwa period (the period from the signing of the Ganghwa Island Treaty in 1876 to the deprivation of national sovereignty), who gave up his sword to avenge his father and sister and was reborn as a gunman, and eventually became a public hero. He became the strongest gunman to protect his beloved lover in the turbulent Joseon. It is a work that depicts the pain and courage of young people in that era. "Joseon Sharpshooter" is a work that Lee Joon-gi and Nam Sang-mi have collaborated again after seven years since "Time of Dog and Wolf", so it has attracted much attention.