Marathon is available in: Korean on Netflix Australia
20-years-old Cho-Won (Cho Seung-Woo) is young man with autism. He lives with his highly protective mother Kyung-Sook (Kim Mi-Sook) and younger brother (Baek Sung-Hyun), who sometimes resents the attention his older brother receives from his mother. Through special schooling and taking part in physical activities, Cho-Won has adjusted relatively well into society. Cho-Won also seems to have a knack for running. After placing third in a race, his mother decides to hire a proper coach to train her son. Cho-Won then decides to take part in a marathon. Cho-Won hopes to break the marathon's fastest record of three hours.