 Eighteen-year-old Do Wan-deuk (Yoo Ah-in) lives with his hunchback father Jeong-bok (Park Su-yeong) and stuttering uncle Min-gu (Kim Young-jae), former cabaret clowns now having to work in open-air markets after the closure of the nightclub they used for many years.Wan-deuk never knew his mother, who walked out 17 years ago, and has become a young brawler.His unconventional high school teacher, Lee Dong-ju (Kim Yoon-seok), who treats all his students with equal harshness, lives on the rooftop next door and is always on Wan-deuk's back.