Tensions run high as Intelligence seeks justice for Olinsky after he's stabbed in prison; Antonio's loyalty is put to the test; Woods looks to take down Voight once and for all. Season Finale.

After tragedy strikes Intelligence, the unit must persevere during an adrenalized manhunt across the city.

In the Season 3 finale, the team investigates the murder of a single mom who was in contact with Voight's now-reformed son, who was himself brutally assaulted. Meanwhile, Roman makes a major decision and Crowley plans to make changes within the unit.

With Kelton’s election all but assured, Voight and his team must go off book in a last-ditch effort to save Intelligence from getting axed.

Voight and the team muster all their expertise to bring down a deadly crime ring. Burgess finds herself in a dangerous situation.

With the suspects still at large and conditions worsening underground, first responders race to reach the trapped victims, while the investigation into the assailants comes into focus. The crossover starts on Chicago Fire S13E11 In the Trenches (I) and Chicago Med S10E11 In the Trenches (II).

Olinsky's daughter remains in critical condition following a massive fire - leaving Intelligence on edge, but more determined than ever to track down the suspect. Voight opens up the case, knowing that he has Stone and his team's full support in the investigation, and all of Firehouse 51 behind him to examine potential origins of the fire. The crossover starts on Chicago Fire S05E15 Deathtrap (I). It continues on Chicago Justice S01E01 Fake (III).

After receiving a distressing 911 call, Burgess enlists the team's help to track down a girl caught up in a sex-trafficking ring.

When a young officer is shot dead in the lobby of an apartment building, Intelligence looks to the latest known offenders who have threatened the police. But when a second officer is killed, the team finds that they are dealing with someone who is highly trained and knowledgeable.

Halstead and Atwater go under cover to prevent military-grade weapons from hitting the street; Voight calls in a favor to clear Olinsky's name for Bingham's murder.

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 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

When Upton and Ruzek answer an emergency call to an abandoned house, their investigation leads them down a dark path.

Burgess gives chase after Roman is wounded by a hooded perp who opened fire on their patrol car and shoots who she thinks is the suspect, but no gun is found at the scene—and the person she shot is a 17-year-old honor student.

The body of a 15-year-old girl is found crushed in an abandoned building after she runs away from a treatment center for troubled girls. Voight sends Halstead undercover as a guard to work from the inside at the center, where he believes the girls are trading sexual favors for something in return.

After encouraging her sister to spend a night out with friends, Burgess wakes to find that Nicole never made it home. As the guilt begins to eat at Burgess, the team in Intelligence bands together to make finding Nicole their main priority.

Halstead's partying with Camila unintentionally puts him in the middle of a drug-related homicide. He's forced to choose between loyalty to his unit and his girl. Meanwhile, Voight finally discovers the mole in his unit.

Atwater goes undercover to take down a gun-trafficking ring, but discovers an officer from his past is undercover in the same organization.

After an explosion rocks the case, the team scrambles to finally take down Escano as everyone nears their breaking point.

An unexpected visitor causes disruption for Ruzek and Burgess amidst an emotional investigation involving an unidentified young girl.

SVU's Benson, Fin and Amaro help with the investigation of a rape-murder that's similar to a decade-old case in New York; and, after he's questioned, a suspect warns Lindsay that the investigation could have unintended consequences. The crossover starts on Chicago Fire S03E21 We Called Her Jellybean (I). It continues on Law & Order: Special Victims Unit S16E20 Daydream Believer (III).

The team is terrorized by a gun-wielding father who is desperate to find his missing daughter. Bunny stirs up accusations of misconduct from Voight's past.

The team investigates a murder in which the victim appears to have been wearing a CPD-issued wire. Burgess works a case with a new partner. Crowley questions Lindsay about the night that Intelligence pursued Justin's killer.

When the team is called to an in-progress bank robbery, they come across Detective Hailey Upton trying to take over the crime scene with her Robbery-Homicide unit - butting heads with Voight in the process. As the robberies continue to be executed around the city, Lindsay is forced to make a decision in the heat of the moment.

When Atwater disappears at the house of a convicted felon, the evidence doesn't look promising - with his belongings and his blood left behind. Intelligence rallies to rescue him before it's too late. And Atwater struggles for survival faced with not only his captor but also a difficult connection to his past.