When Vic and the Strike Team fall short of discovering which bills from the money train are marked, there is only one option left - to steal the safe, which contains the list of marked money, from Aceveda's office. The scheme gets interrupted when one of Vic's open cases, which involves a missing girl, is suddenly linked to a Narco Corrido song. The discovery of Narco Corridos, (popular songs in Mexico that depict crimes that have actually happened), gives Vic the blueprints behind several crimes. He must now work with Dutch and Claudette to find the singer and finally close his case. With the help of the Decoy Squad, they finally find the missing girl at her boyfriend's house where she has been hiding out. Meanwhile Claudette takes down a meth lab that is using illegal immigrant women as slave labor. While investigating the crime described in one of the songs, Vic comes face to face with an old fling and sparks fly. Danny and Julien are docked for going off the grid on the Tommy case and are forced to handle the annual inventory that creates some trouble for Dutch when a laptop is missing. David pays a late night visit to his cousin, Rigo's, house. He confesses to Rigo about the rape and Rigo recommends that there is only one way to take care of the problem.
The Shield breaks the conventional formula of the cop genre. It plays out in a tough, morally ambiguous world in which the line between good and bad is crossed ever day. The series focuses on the tension between a group of corrupt but effective cops and a captain torn between bringing them down and advancing his own political ambitions.
The Shield stars rogue cop "Det. Vic Mackey", leader of the elite Strike Team unit, who is effective at eliminating crime but who operates under his own set of rules. "Captain David Aceveda", the young precinct head who doesn't like Mackey's tactics and wants to bust him off the force. And "Det. Claudette Wyms", a veteran detective who understands Mackey and knows how to play both sides of the fence.