|Big Friends, Big Enemies|
|Season 4, Episode 4|
|Airdate||October 12, 2016|
|Written by||Gwen Sigan|
|Directed by||Rohn Schmidt|
All Cylinders Firing
A War Zone
Big Friends, Big Enemies is the forth episode of the forth season and the 65th overall episode of Chicago P.D.
The Intelligence unit investigates a drive-by shooting, which kills a local rap star. Voight initially suspects a terrorist group may be involved, but, after a second shooting in gang territory, the unit considers the possibility that both crimes are part of a gang war. Meanwhile, Burgess spots Atwater's younger brother while out visiting potential shooters and targets.
- Jason Beghe as Sergeant Hank Voight
- Jon Seda as Detective Antonio Dawson
- Sophia Bush as Detective Erin lindsay
- Jesse Lee Soffer as Detective Jay Halstead
- Patrick John Flueger as Officer Adam Ruzek
- Marina Squerciati as Officer Kim Burgess
- LaRoyce Hawkins as Officer Kevin Atwater
- Elias Koteas as Detective Alvin Olinsky
- Amy Morton as Desk Sergeant Trudy Platt
- Li Jun Li as Officer Julie Tay
- Zoe Ishmael as Vinessa Atwater
- Ahmad Nicholas Ferguson as Jordan Atwater
- Landree Fleming as Jenny Barcles
- Saul Huezo as Luis Garza
- Al'Jaleel McGhee as Bird
- Messiah Equiano as Mark "Markey" Caines
- Opal Staples as Moira Kenton
- Eugene Parker as Joe Kenton
- Jose Joey Abril as Mal
- Jimmy Pennington as Greg Penley
- James Farruggio as John Morin
- Jasmine Bracey as Jovanna
- Ahmir Elijah as Bryant
- Samantha Pauly as May
- Skyler Adams as Nick
- Yung Sirc as TK Ice
- Rich Holton as Corey
- Jason Tolliver as Southside Shot-Caller
- Jeremiah Garcia as Alex Santos
- Eibur Stepney-Manuel as Grandmother
Atwater: You shoved this life down his throat.
Burgess: All you should be saying to me right now is 'I'm sorry, I screwed up.'
Halstead: It's a wonder he got shot.
Dawson: I've seen too much of this
Voight: Whoever did this just wanted bodies
Voight: That ain't youth. That's hate.
Ruzek: You can learn from my mistakes.