Akeanan is an outstanding school in all aspects: education, sports… and secrets.

Traffic comes to Akeanan to look for his sister Fah, who disappeared months prior and with neither the police nor the school finding any trace of her. In the course of his investigation, Traffic finds himself in Room 4/6 and meets the outsiders of the class: bad boy Andrew, the quiet Highlight, the strong and powerful Title, friendly and playful Jim Bae, and the academic genius Buntad.

Traffic gets an invitation from their teacher to join this group of boys, the secret shadow society known as Blacklist, dedicated to investigating the mysterious occurrences in their school.

Together, Blacklist will find out not just what happened to Fah but will also slowly uncover the deep dark secrets of Akeanan School.