Chicago P.D.'s Production Designer Dishes About Where the Show Is Filmed

The heart of the series is the 21 District Station and, while some exterior shots were filmed at the University of Illinois Chicago Police Station on Maxwell Street, the majority of the station's action is currently filmed at Cinespace Studios.

Yes, that means most of the Chicago P.D. action takes place on several stage sets. 

Van Horn explained: "The 21 District Station is comprised of five distinct sets: Front Desk, Intelligence, Roll-Up, Motor Pool, and Lockup, spread over two sound stages plus a maintenance building, totaling over 15,000 square feet."

Van Horn told NBC Insider that the most elaborate stage set is Intelligence, the spot Chi-Hards watch the unit collaborate on the latest high-stakes case.

For instance, when Hank Voight (Jason Beghe) has an announcement to make, the unit's Bullpen is where the squad gets the lowdown.

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"The Intelligence set houses the Bullpen (where our team meets every episode), Voight’s Office, Interview 1 and 2, Observation, Locker Room, and War Room (a.k.a, the Wire Room), with interconnected hallways," Van Horn explained.

Molly's was inspired by and originally filmed at the real-life Bucktown establishment Lottie's Pub. However, after the One Chicago bar became a local tourist attraction, production recreated Lottie's unique charm at a stage set at Cinespace Studios. 

On the show, Molly's is owned and operated by Chicago Fire firefighters Christopher Herrmann (David Eigenberg) and Randall “Mouch” McHolland (Christian Stolte) with P.D.'s Trudy Platt (Amy Morton) (who is McHolland's wife). The bar is a nod to the many neighborhood establishments sprinkled throughout the Windy City boasting Midwest charm, string lights, and a fair-priced pint. 

Lottie's remains a local hot spot, famous for its open mic nights and high-energy playlists.

That said, some One Chicago scenes at Molly's require a trip to the neighborhood establishment to guarantee authenticity. In NBC Insider's chat with Chicago Fire producer Demetra Diamantopoulos, she revealed that production still pays the occasional visit to Lottie's.

"While we have a stage set based on Lottie’s at our studio, we still film exteriors at the real Lottie’s from time to time..." Diamantopoulos revealed. "They were chosen, way back when, for their quintessential Chicago look, inside and out. Bucktown is one of our favorite Chicago neighborhoods."

"While the show has shot some beautiful Chicago landmarks — Tribune Tower, Union Station, Cloud Gate, Museum of Science and Industry, Lincoln Park— some of my favorite locations have been an abandoned L station, the 'Capone' tunnels under The Green Mill, the magnificent lobby at the abandoned Uptown Theatre, and various L train tunnels," Van Horn told NBC Insider.

While the Chicago P.D. cast has already filmed in some of Chicago's most iconic locations. NBC Insider was keen to learn which they might head in future episodes — and Van Horn thinks big. 

"A wishlist for our show would include places we probably could never get into," Van Horn explained, adding: "Like the water intake towers off the shore of Lake Michigan, the network of underground tunnels near the Chicago River, or the Marine Unit at Navy Pier."