Seul-gi, who had been suspicious of Je-na's death, finds out the whole story of the case while looking for Soo-jin and begins to cooperate with Jae-yi. Kyung-yi and Ye-ri each approach the case in their own ways.

During the final exam, the rankings of the entire school change drastically, and Seul-gi is frustrated because she cannot figure out Jae-yi's intentions. As Jae-yi said to use Seul-gi, Tae-jun makes a deal with Seul-gi by offering her a killer college entrance exam question.