Da-In Jeong, a national gymnast at Daehan School of Kinesiology, starts investigating the doping-induced suicide of Eunju Lee, his childhood friend.

During the investigation, he learns that there was some huge conspiracy behind her death. In addition, he also finds out that a lot of sports club students are addicted to a drug that enhances their physical abilities a great deal and that those students have already become pawns of the drug dealer.

Da-In makes up his mind to keep investigating to reveal the truth of Eunju's death and eradicate the source of drug distribution all around the school...