A mounting street war threatens a community-center project that Atwater is trying to get off the ground.

Burgess works an extra shift at the 13th District and gets caught in the middle of a drive-by attack on refugees. The team works together to track down the shooter and uncover the true motive behind the attack.

As Atwater finds himself distracted by a past case, a CI from his past resurfaces with a tip on a string of armed robberies that are raising concerns.

As the team investigates a convenience store robbery, the evidence leads them to an unusual pair of suspects, revealing a dark personal drama and another potential victim. Burgess slowly makes strides tackling her past trauma.

Cook works with a confidential informant for the first time in a robbery-murder case with links to a star college athlete.

When a murder implicates a diplomat, the FBI stands between Intelligence and justice.

The team investigates a rash of car jackings and finds the truth is more complicated than they realize. Burgess makes a discovery about a previous case that will change her life forever.

When a local business owner is gunned down in his shop, it becomes personal for Atwater, who patrolled the neighborhood as a young cop. Dep. Supt. Samantha Miller comes to Voight with a special request about Andre Cooper.

Voight employs his new informant to help solve a tricky drug trafficking case. Atwater, who once again struggles to reconcile his personal and professional life, reaches a decision.

Ruzek's search for the daughter of an old family friend leads the team into a serious drug investigation. Burgess and Ruzek struggle to move on from the emotional aftermath of Makayla's abduction.

A shocking ambush at a funeral leads the team into a heated investigation to find the shooters. Much to Atwater's surprise, he must rely on someone from his past to help in the investigation, dredging up old memories and revealing new truths.

Voight and the team help ASA Nina Chapman pursue a drug runner who dodged prison years ago after Chapman's informant mysteriously disappeared. The investigation takes a turn when Voight uncovers a damaging secret from Chapman's past.

Tasked with shadowing a crisis prevention team, Upton finds her approach to policing at odds with the team's mental health clinician. Voight stands by Upton as she continues to struggle in her personal life.

Ruzek gets mixed up in a case after a late-night poker game is raided. Afraid of becoming like his father, Ruzek struggles to stand down and allow Intelligence to carry out the investigation.

Torres' personal involvement with an informant jeopardizes his safety and threatens to expose an undercover operation.

The search for the suspect in a shooting uncovers a surprising personal connection to Atwater and Val, raising questions about their relationship status.

Voight and team head to a house that’s been associated with a number of top gangs. Events at the search result in Ruzek, being encouraged to seek some counseling which may have lasting repercussions professionally and personally. Meanwhile Halstead’s temper rises when he comes in contact with some unwelcomed people from his past.

Bob Ruzek is the first to arrive on the scene of a double murder. Intelligence arrives to take over the investigation and tensions arise as Bob needs to hand over the case to his son and Voight. Lindsay's new gig has her planning a trip to Bolivia for an undercover investigation that could be for an extended amount of time. Burgess and Roman realize they need to put past events behind them so it doesn't jeopardize them going forward.

When Voight's card ends up in the hands of a murder suspect, he aims to protect the man at any cost.

The team responds to the shooting of a 5-year-old girl and must work the case while facing new obstacles that come from the heightened attention on police reform. Atwater is targeted by a group of officers who want to hurt him for standing against the blue wall. Voight questions whether he's cut out for a new form of policing as he manages oversight from the CPD's deputy superintendent.

As the team works to solve a deadly shooting in Burnside, Atwater realizes he has a very personal connection to the case.

Ruzek reunites with an old colleague to take down a crime ring but when things don’t add up, Voight and Burgess do some investigating of their own.

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.

When a convicted murderer hijacks a prison van, the team scrambles to find him and the abducted prison guard before it's too late. Burgess questions Ruzek's motives in a case, creating tension between the two.

Sean O'Neal surprises Upton with a call from prison, revealing sensitive information. Meanwhile, the team quickly mobilizes to stop a crime in progress before it's too late.