A high school student dreams of becoming an architect. However, she had to drop out of school after suffering from brutal school violence. Years later, the perpetrator gets married and has a kid. Once the kid is in elementary school, the former victim becomes her homeroom teacher and starts her thorough revenge towards the perpetrators and bystanders of her bullying days.

• Song Hye-kyo
• Lee Do-hyun
• Lim Ji-yeon
• Yeom Hye-ran
• Park Sung-hoon
• Jung Sung-il
• Kim Hieora
• Cha Joo-young