Aozora Okami is the teenage son of a boxer who was sent off to fight in the Second World War. After the bombings, he and his younger sister Akari are left as war orphans doing their best to survive. When its discovered Akari has tuberculosis, Aozora goes to confront some men who stole from him. It is then that his ability to get back up after taking a punch and throwing a right hook are noticed by a woman who thinks he’s suited to become a boxer. In postwar Japan, Aozora will swing his fists to protect his little sister!