2021
S01E16 finale
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.
Yoon Su finds out that Seung Yoo solved the question. But he tries to keep a distance from her, saying he doesn't like math. Yoon Su gives him another math problem, and the problem allows them to connect and communicate. Meanwhile, a math competition is held at Asung High to select the rep student to participate in the International Mathematics Olympics.