Still reeling from the death of informant Anna, Voight faces a new threat as he tries to keep the neighborhood clean. New wrinkles develop in the Upton, Halstead and Voight dynamic. The team gets a new chief.

The team investigates a string of brutal pharmacy robberies, and Halstead connects with one of the victims about their Army careers. Upton suspects there is more to the story and confides in Voight.