Su-ji is trapped by Ha-rin's blackmail. She feels bad keeping a secret from Ja-eun. The class goes on a school trip. Tension builds until everything explodes in a game of survival.

The students are upset about a violent assault that occurred during the class trip. A powerful allyship gives Su-ji hope. Su-ji acts on her plan to take down Ha-rin.

The big day has arrived. Issues develop between Su-ji and her friends. A winning move is made against Ha-rin. The public learns about the Pyramid Game. Ha-rin finally contacts Ja-eun.