
Chicago P.D.'s Intelligence Unit, led by Sgt. Hank Voight, investigates the city's most formidable offenses -- drug trafficking, organized crime, high-profile murders and other large-scale felonies. The squad -- made up of Voight, Trudy Platt, Kim Burgess, Adam Ruzek, Kevin Atwater, Jay Halstead and Hailey Upton -- is committed to protecting the city and seeking truth, but in the midst of a changing criminal justice system, the team struggles to maintain peace in the community. Voight must learn to adapt to a shifting sociopolitical climate and embrace new tactics to crack down on crime in the city he loves.

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

Antonio believes a Colombian gang is involved in his son's kidnapping; Halstead learns new information about Lindsay; Voight offers Antonio a new way to get information about Diego's whereabouts.

Voight and the team check out a house that has been associated with a series of gangs; people from the past cause Halstead's temper to rise.

The team responds to the shooting of a 5-year-old girl and must work the case while facing the heightened attention on police reform; Atwater is targeted by officers who want to hurt him for standing against the blue wall.