The culprit responsible for setting fire to Wan Seung's house turns out to be a little boy named Won Jae. As a copycat of Na Jin Tae, Won Jae tries to set fire to a truck. When he misses it, he throws a firebomb at his friend's mom instead, leaving her severely injured. Wan Seung and Seol Ok have to fight against Won Jae's father, who's an influential lawyer to prove that what Won Jae did is wrong.
날카로운 추리로 방화범의 정체를 밝혀낸 설옥!
하지만 범인은 촉법소년에도 해당 안 되는 9살 소년이다.
설옥은 범죄를 막기는커녕 가해자를 법으로 처벌할 수 없는 현실에 좌절한다.
과연 설옥과 완승은 피해자의 억울함을 풀어줄 수 있을까?
