Jason Beghe (Hank Voight)Jesse Lee Soffer (Jay Halstead)Patrick John Flueger (Adam Ruzek)Marina Squerciati (Kim Burgess)LaRoyce Hawkins (Kevin Atwater)Amy Morton (Trudy Platt)Jon Seda (Antonio Dawson)Elias Koteas (Alvin Olinsky)Tracy Spiridakos (Hailey Upton)Sophia Bush (Erin Lindsay)Brian Geraghty (Sean Roman)Samuel Hunt (Greg Gerwitz)Lisseth Chavez (Vanessa Rojas)Chris Agos (ASA Steve Kot)Stella Maeve (Nadia Decotis)Markie Post (Barbara 'Bunny' Fletcher)Nick Gehlfuss (Will Halstead)Barbara Eve Harris (Emma Crowley)
Michael Brandt, Derek Haas, Dick Wolf, Matt Olmstead
District 21 of the Chicago Police Department is made up of two distinctly different groups. There are the uniformed cops who patrol the beat and go head-to-head with the city's street crimes. And there's the Intelligence Unit, the team that combats the city's major offenses--organized crime, drug trafficking, high-profile murders, and beyond.