
S01E01 Fermat’s Last Theorem
At Asung High, Yoon Su’s new workplace, she gives a tricky question for students who want to join the math club. While no one in the class got the question right, a correct answer sheet...
Seung Yoo tries to bring Yoon Su out into the world from her rut by getting close to her heart, just the way she helped him. Meanwhile, Yoon Su keeps her identity hidden while collecting evidence of Noh Jung Ah's corruption. However, when Yoon Su's identity is in danger of getting exposed, Seung Yoo stands in front of her.
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 corruptions in school and to regain one's reputation as a teacher.