Sim Hyun-seo

Two friends in the past were victims of serious school bullying. One could not resist his trauma, and becomes a serial killer, walking in the path of revenge. Another one tries his best to overcome the trauma and becomes a police detective. He now faces tragic fate to risk his life to capture the serial killer.

In 2001, Lee Gyeong-hwan and his mother move from rural Yeongcheon to the city of Daegu to leave behind a broken marriage and hurtful rumours. Reticent and shy, he struggles to acclimatise but his seatmate happens to be Jae-min, the cool class president who takes Gyeong-hwan under his wing. While they quickly bond over a shared love of Japanese culture, particularly the music of Globe, Jae-min's affectionate and open attitude allows Gyeong-hwan to relax and reveal his feelings in a world where he must hide them.

Yuwol, who is dancing all the time, has been considered to be the main culprit behind the dance virus at his school. The teachers calling for order begin to trace him.