The Shield plot
Detective Vic Mackey leads a team of cops who are highly successful in fighting crime. They only work according to their own rules, in a very controversial way and they do not shy away from a tough approach. Commander David Aceveda is the youngest district chief, who is not happy with Mackey's way of working and would rather see him go than come. The only thing holding him back are the very good results of the team and Mackey's influential friends.