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

A homicide in the neighborhood where Burgess and Ruzek reside forces the team to investigate complicated relationships within the tight-knit community they call home.

The Intelligence Unit races against time when a man from Torres' own neighborhood is violently abducted.

Voight and the Intelligence Unit focus all their effort and resources into investigating the disappearance of an exotic dancer who served as a long-time criminal informant for their team

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.

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

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.

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.

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.

After discovering the true cause of the high-rise fire, Intelligence races to find the man responsible. And for Halstead, it’s personal. The crossover starts on Chicago Fire S07E02 Going to War (I) and Chicago Med S04E02 When to Let Go (II).

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.

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.

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.

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.

Torres finds himself in the midst of a murder case that hits close to home and threatens to expose his troubled past. As he struggles to reconcile his old life with his new one, Voight keeps a watchful eye.

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.

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 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.