On Christmas, high school student Bae Joonyoung discovered the dead body of his classmate Lee Sowoo buried under snow at school. Prior to his death, Sowoo had gotten into a fight with class bully Choi Woohyuk. Sowoo was sent to talk to Han Kyungmoon, the legal counsel for the school’s foundation, who wanted him to hide damaging information. Han Jihoon, Sowoo's questionably only friend, played the cello at Sowoo’s memorial service, and Go Seoyeon got an anonymous accusation claiming Sowoo's death was a murder instead of a suicide. With school officials and authorities trying to rule the death a suicide, Seoyeon and her friends decided to investigate Sowoo’s death on their own by having an in-school trial. Meanwhile, Joonyoung shyly falls for Seoyeon while fate pushes her towards Jihoon. To make Joonyoung's life a little less miserable, fate also decided to throw Jung Heejung into the mix.