
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 and Ye Rin prepare in earnest for the Math Olympics. Jung Ah and Min Jun teach Ye Rin the means to win, and Yoon Su finds out about the corruption in the competition. However, Yoon Su goes to Jeju Island with Seung Yoo to help him with the contest. On the same day, Ye Rin arrives at Jeju Island for internship activities for the competition.
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.