Akif Erdem enters the 12A class as a physics teacher at Kucukkapi high school and detonates a bomb that will take the students hostage and sever their connections with other parts of the school. No one was hurt in the blast; all class 12A and law enforcement will try to find out why Akif did this - Akif will teach everyone a great lesson.
After Mevsim is revealed to be the owner of the account who first shared Ruya's video, Akif now gives the students a new homework: Either tell me who took the video, or 5 other students will die.