Kwon JiYong- a young police officer with great ambition but his righteousness caused him to be deployed to work undercover in a prestigious school that is full of arrogant students that is full of secrets.

Choi SeungRi- An A* student who is just like a walking encyclopaedia and possesses many skills.

Kang DaeSung- The friendliest person that everyone has ever met.

Choi SeungHyun- SeungRi's adopted brother, who is also the most popular guy in the school.

* All of them are in class 2A *

Dong YoungBae- The form teacher of class 2A.

It's been reported by the local news that the body of Lee Hyunwoo, a famous detective that has retired from the police force, was found near the outskirts of the forest. It is most likely that he had committed suicide. The evidence that is found indicates that he had died from excessive bleeding due to being slashed at the throat. Not only that, there is a letter beside him for his son....

“What a nice cover up.” I smirked at the news as I put down the newspaper. Everything is under my control.

10 years later the incident was forgotten by most of the citizen but someone is not ready to let go and investigates.