Chicago P.D.

Bad heroin is causing overdoses in Chicago, and Intelligence is a man down with Voight suspended. Antonio takes charge, but Ruzek undermines his authority.

After discovering the true cause of the high-rise fire, Intelligence races to find the man responsible. And for Halstead it's personal.

Politics get in the way as the team tries to rescue a teenage girl kidnapped by a robbery crew. Voight and Platt try to exonerate Olinsky.

A ride along goes sideways, and Burgess is faced with a difficult choice: follow the advice of Voight, or a potential new ally.

While undercover, Ruzek discovers his father is working for a suspected drug dealer and is forced to ask the question: is his dad involved?

The wife of an alderman is beaten to death, and Voight is under pressure from First Deputy Superintendent Brennan to close the case. To elicit a confession, Upton tells a dark story about her childhood.

Intelligence suspects the leader of a local mosque is behind the bombing of an Army recruitment station. After a second explosion, Voight urges Halstead to follow the facts and not let his time in the service cloud his judgment.

While CPD tries to take down a drug kingpin, Atwater faces a tough choice between doing what's required to solve the murder of a young dealer and what's best for the community.

In an attempt to dig himself out of a hole and save someone close to him, Antonio crosses a line that puts the entire team at risk.

Voight and Ruzek lock horns over how to handle the aftermath of the Antonio situation. Meanwhile, a series of violent carjackings turns deadly, and Ruzek must rely on a C.I. he grew up with to help solve the case.

When a defense attorney is murdered after a fundraiser, Intelligence must confront the world of campaign finance, which makes them reconsider their decision to back the current pro-police mayoral candidate.

While chasing a heroin supplier, CPD crosses paths with a convicted criminal recently released on a technicality. Halstead's history with the man threatens the team's ability to put him back in prison.

Atwater goes undercover to bring down the longtime head of a criminal enterprise and becomes entangled in a situation that tests his allegiances as well as his conscience.

The team travels to a Wisconsin gun show to take down a supplier who's manufacturing "cop killer" machine guns. Before going undercover together, Burgess discovers that Upton is dating Ruzek.

Using information from Chicago Fire's Cruz, Intelligence chases down the robbery crew that's been using the lockbox key. Voight is under pressure to bring the crew to justice without tarnishing the reputation of a murdered firefighter who might have been involved.

Voight's "stay out of politics" stance is challenged as Intelligence uncovers the details surrounding a prolific serial killer.

A mayoral candidate is shot by an unidentified sniper, and CPD races to catch the shooter before he can take out his next target.

With the threat of a gang war looming, Voight and Ray Price must organize a peace summit to end the bloodshed before more innocent people get hurt. Burgess evaluates her future with Blair.

Intelligence's investigation into the murder of Burgess' boyfriend threatens to reveal a dark side she was unaware of, but the real motivation for his murder uncovers a much more unsettling truth.

A violent crew is hitting pharmaceutical delivery trucks and stealing drugs, but their motivation is more complicated than just money. The case tests Upton and Ruzek's relationship.