This movie details a single day in the life of a young young LAPD rookie cop.
Alonzo Harris (Denzel Washington) is a highly decorated LAPD narcotics officer and Jake Hoyt (Ethan Hawke), a young and inexperienced cop is assigned to him for evaluation.
Jake quickly discovers that the highly decorated and well respected Alonzo Harris is not the clean and honest cop that he expected him to be and that he does not give a damn about ethics in the course of his duty as a police officer. It is clear that the two of them have divergent views about how to enforce the law.
When it became obvious that Alonzo is engaged in activities that are much dirtier and deadlier than law enforcement, officer Hoyt must sooner than he expected choose to either stand up for the principles that made him to join the force, or go against them. All within twenty four hours.