William Gines

Severide springs into action when gunmen open fire on the subway. Gabby Dawson learns a harsh lesson on her first day as a firefighter.

A young bystander is shot during a difficult operation. Chief Lugo reviews the shootout and Halstead becomes a key player in the outcome.

Voight and the team pursue a ruthless crime ring whose business has hit close to home; as they dig deeper, the extent of the danger becomes more apparent; Deputy Superintendent Samantha Miller second-guesses her decisions.