After New York City teacher Trevor Garfield (Samuel L. Jackson) is nearly killed when he is stabbed by one of his students, he moves to Los Angeles to start again. Teaching in Los Angeles, however, proves to be an even greater challenge after Garfield discovers that the classrooms are ruled by the local gangs and that the school administration is too fearful to intervene to stop the violence and bullying. With all else failing, Garfield has to learn to play by the rules of the street when the situation gets out of hand after the murder of one of the gang leaders and threats of violence directed at fellow teachers.