The first One Chicago crossover since 2019 will air on NBC on January 29. 2025 – and showrunners have promised something "a little new for us," as some of our favorite characters face heartache.
"Hats off to the writers, they did a really nice job of making this thing feel really cohesive and interwoven, which is fun, and I think it's going to be a little new for us," Chicago PD showrunner Gwen Sigan told HELLO!
"Once we started getting into trying to figure out the emotional stakes and asking, 'How do we ramp up the tension and the emotions and stakes throughout the entire three hours?', it started to be clear that we have so many interesting relationships on all three shows, and [we needed] to really dig into those relationships."
The first trailer for the upcoming episodes teased uncertainty and heartbreak for three couples, with Lieutenant Stella Kidd (Miranda Rae Mayo) and Police Officer Adam Ruzek (Patrick John Fleuger) on the L train during an explosion.
Detective Kim Burgess (Marina Squerciati) Adam's fiancee, and Lieutenant Kelly Severide (Taylor Kinney), Stella's husband are left above ground unsure of if their loved ones are safe, while the clip showed Desk Sergeant Trudy Platt (Amt Morton) wheeled into surgery as her husband, Lieutenant Randall 'Mouch' McHolland (Christian Stolte) watches on in tears.
Gwen revealed that the writers chose these couples because it was an opportunity to show "family and unity and partnership, and thematically, it was really interesting to us, the great tension of [these couples] being separated and all these fun things that we could really write into".
As for other pairings fans can expect to see, Gwen shared that there are "some fun scenes" with Doctor Archer from Chicago Med and the Intelligence Unit.
"He gets to be with our team and with a lot of the firefighters in a section, which is really fun, seeing him in a different light. And I also really like the Stella Kidd and Ruzek pairing because that's one that I haven't really seen, and they have quite a few scenes together," she said.
As well as Kidd and Ruzek, and Archer and the Intelligence Unit from PD, Gwen shared that the writers have "definitely tried to find intentional moments for characters".
The last couple of crossovers, I don't think had as many scenes where you'll be watching and you'll forget what show you're in because all of the characters are in the scene," she said.
A proper crossover has not been able to happen due to the COVID-19 pandemic putting stricter restrictions on TV productions.
When things began to return to normal, the writers were then unable to find the right story that would work, with Gwen admitting that process is "essentially a movie that you're trying to break but in a way that's producible for three separate television shows".
There have only been smaller crossovers, with one or two characters appearing in another show.
The official logline for the episode reads: "When a gas explosion rocks a high-rise, Chicago’s first responders come out in force to rescue hundreds of civilians. It’s the calamity beneath the surface, however, that sends our heroes on a race to save 40 people trapped deep underground, including two of their own." .