Byung-gu is a former professional boxer who was once in the spotlight as an up-and-coming boxing champion. When a dire mistake gets him removed from the boxing association, Byung-gu makes ends meet by doing different odd jobs at a gym.

Although he is eager to start boxing again, Byung-gu gets diagnosed with ‘punch drunk syndrome,’ a condition caused by repeated cerebral concussions. One day, an upbeat new member of the gym named Min-ji arrives and volunteers to help Byung-gu. With her help, Byung-gu kicks off his most reckless challenge in life to perfect his unique style of ‘Pansori Boxing.’