0th Correctional Officer

Ji-hoon, a former member of a secret special forces unit under the Republic of Korea Army Headquarters’ Special Operations Planning Office, returns from a long overseas deployment only to receive devastating news: his younger sister Ji-yoon has died, and the perpetrator is allegedly her boyfriend, Seo Min-jun.

Unable to easily accept the fact that his sister is dead, Ji-hoon initially believed in Min-jun’s innocence. He discovers that Min-jun took the blame and went to Yeoксeon Prison in order to find the real culprit who killed Ji-yoon.

However, Min-jun ultimately meets his death in prison as well… Ji-hoon becomes a prison guard and heads to Yeoксeon Prison to uncover the secrets behind the unjust deaths of these two people. This appears to be a revenge/mystery thriller webtoon where the protagonist infiltrates a prison as a guard to investigate the suspicious deaths of his sister and her boyfriend, suggesting there’s a deeper conspiracy at play.