After zeroing in on the suspect responsible for the bioterrorism that’s gripping Chicago, the PD prepares to undertake their biggest manhunt yet. Upton is torn between helping track down the perp and providing emotional support to the scared young girl that needs her. Voight fears his team is being sent on a wild goose chase.
After a botched carjacking turns out to be something much bigger, Voight’s unit goes toe-to-toe with a smart drug kingpin who only works with women. New recruit Vanessa Rojas struggles with the transition from undercover to Intelligence, but the new case gives her a chance to play to her strengths.
When Atwater goes undercover in a dangerous South Side drug syndicate, he learns there may be more to its kingpin than meets the eye. Halstead tries to join Atwater undercover, but finds himself at a disadvantage. Voight petitions the brass to show Ruzek leniency in his court case.
Season Premiere. When Kelton is found murdered, Voight’s grudge against the mayor-elect puts him under suspicion. Upton and Halstead are eager to prove their sergeant’s innocence, but the more evidence they gather, the closer they come to doing the opposite. After making bail, Ruzek searches for a missing Antonio.
Antonio (Jon Seda) struggles with his guilty conscience as he tries to take down a major drug dealer. In order to protect his team, Voight (Jason Beghe) takes a big shot at Kelton (guest star John C. McGinley).
A violent crew is hitting pharmaceutical delivery trucks and stealing drugs, but their motivation is more complicated than just money. The case tests Upton (Tracy Spiridakos) and Ruzek’s (Patrick John Flueger) relationship.
Intelligence’s investigation into the murder of Burgess’s (Marina Squerciati) boyfriend threatens to reveal a dark side she was unaware of. But the real motivation for his murder uncovers a much more unsettling truth.