Lesson of the Evil (Aku no kyôten) theatrical trailer - Takashi Miike-directed movie

Seiji Hasumi (32) is an instructor at Shinko Academy, a private high school. He is a model teacher, extremely popular with the students and well respected by the faculty and the PTA. However, one of the students, Reika Katagiri (17), feels something menacing lurking beneath his shining reputation. Hasumi brilliantly solves one problem after another, from a teacher-student sexual harassment to group cheating to bullying, and starts to take control of the school. Specifically, the boss of the bullies gets expelled because of his violent behavior. A "monster parent" dies at home in a fire started by an arsonist. The problems go away, but Reika is uneasy about the way they are solved. Masanobu Tsurii (55), an unpopular teacher in the school, despises the popular Hasumi. He starts investigating Hasumi's past and discovers that many people he was involved with have already died. Hasumi, who had hidden listening devices around the school, finds out how Tsurii is looking into his past, so he kills him one day on the train and makes it look like suicide. Hasumi also murders a male student, who was trying to get back at Hasumi for catching him cheat on a test. In his true nature, Hasumi is a psychopath, a man who cannot feel empathy toward other people. Since he was a child, he has killed people who got in his way. He even killed his own parents when they realized what he was doing. Soon, Hasumi becomes physically involved with Miya Yasuhara, a female student who he helped in a sexual harassment incident, and Miya starts to sense his evildoings. Hasumi finds out about Miya's suspicion and decides that she must be eliminated...