- A sexual scandal between a math teacher and a student in a prestigious high school ended in tragedy. 4 years later they meet again, now as adults, to reveal the corruption in school and to regain one's reputation as a teacher.
Ji Yoon Soo is a high school math teacher with a bright smile and a positive impression of others. She is a hard-nosed and stubborn person who has to push ahead with the decisions she has made. She is a math geek who loves solving difficult problems and teaches students to purely love math.
Baek Seung Yoo is emotionless and has no light in his eyes. He used to be a math genius who appeared on a quiz program at the age of five and surprised the world by solving college-level math problems. He was admitted to MIT at the age of 10 but dropped out at the age of 12, and suddenly disappeared.
Kim Sang Hyub
Im Soo Jung
Lee Do Hyun
Choi Dae Hoon
Oh Gwang Rok
Woo Da Vi