A drug dealer with a vendetta disrupts a detention at a local school after the hosting teacher witnesses him murdering one of her students. It's up to this tough teacher and her resourcefulness to save the day.

Teacher Gloria Abraham witnesses the murder of a student by a local drug dealer, Oscar Reyes, while on the way to work. After agreeing to testify, she is then targeted by the dealer and his thugs. They decide to take care of her while she is overseeing Saturday detentions at the school. Will she and her students survive detention?