Joon is arrested for the murder of the top student at his prestigious school. When he is released, Joon holds students accusing him of the crime in a room and forces them to reveal their dark secrets.
| Actor | Role |
|---|---|
 Sung JoonYoo-jin Taylor | Yoo-jin Taylor |
 David LeeKim Joon | Kim Joon |
 Cho Seong-haPark | Park |
 Kim Kkob-biJeong Soo-jin | Jeong Soo-jin |
 Kim KwonHan Myeong-ho | Han Myeong-ho |
| SSeon Joo-ahKang Mi-ra | Kang Mi-ra |
 Nam Tae-booChoi Bo-ram | Choi Bo-ram |
 Park Hae-joonDetective Choi | Detective Choi |
 Ryu Kyung-sooPark Jeong-jae | Park Jeong-jae |
 Park Hyun-youngTeacher Kim | Teacher Kim |
 Kil Hae-yeonJoon's mother | Joon's mother |
 Hwang Jeong-minMyeong-ho's mother | Myeong-ho's mother |
| PPark Nam-heeJeong-jae's mother | Jeong-jae's mother |
 Oh Jung-wooKang Chang-min | Kang Chang-min |
 Kim Jae-rokPrincipal | Principal |
| KKim Ho-yeonSoo-jin's mother | Soo-jin's mother |