Los héroes del mal (2015)

Three teenagers, brought together by bullying, indulge in petty theft, sex and drugs. They inevitably realize they can resort to violence to take revenge on everyone who has humiliated them: students, teachers and other outcasts. One of them escalates to killing, and desires to kill again. Anyone can become his next victim. The other two face the question: should they resort to violence to stop the killings?