High Cookie

The top student in Class S of Jeonghan High School mysteriously dies. Knowing the real cause of death, Min-young struggles to cover up the incident.

Soo-young happens to give the mysterious cookie to someone at work. But this one cookie becomes a threat to the sisters' lives.

While investigating Yoo-jung's death, a detective notices that the cookie is at the center of the case. Min-young attempts to derail the investigation.

A detective visits Soo-young after discovering the cookie's connection to Min-young. Infuriated by the accusation, Soo-young looks for the truth.

Seong-pil, a consultant at the school, calls Min-young privately and offers to help her. Meanwhile, Soo-young's investigation of the cookie leads her to the school.

With Seong-pil's help, Min-young tries to get out of the cookie business and turn herself in. However, her plans go awry when she encounters an unexpected person.