After a series of brutal murders, Sergeant Hank Voight and District 21 go after a Colombian drug cartel cleaning house in Chicago, but complicated histories and unit rivalries begin to surface.

Antonio is sure the Colombian gang is involved in his son's kidnapping and Voight offers him a way to gain information; Halstead discovers some new information about Lindsay.

Voight and the team take a look at a house that has been linked to a series of gangs; Halstead struggles to maintain his composure when he is confronted by people from his past.

The team investigate the links between a crime lord and a deranged artist who may have been using his skills to create something dangerous.

The Intelligence Unit discover a drug smuggling operation when a balloon filled with cocaine bursts inside a student drug mule; tensions rise between Olinsky and Ruzek.

Voight and Antonio receive help from SVU agents in New York as they try to find a suspect responsible for a number of rapes and murders.