Teaser for Chicago Fire, PD and Med offers first look at Dermot Mulroney's new boss (exclusive)

The fact that all children are going back to school on Wednesday evening can only mean one thing: It's time to go back to Chicago!

In an exclusive teaser for the new seasons of Chicago Med, Chicago Fire And Chicago PoliceAll of the fan-favorite characters return to work, in two cases even with new co-stars.

The footage shows a first look at Dermot Mulroney as the new fire chief, called Dom Pascal, following the promotion of Chief Wallace Boden to deputy commissioner of the entire Chicago Fire Department – ​​and the retirement of Eamonn Walker at the end of Chicago Fire Season 12.

“Let's go, team!” Pascal says in one scene. But in another, he notes, “There's going to be changes around the fire station.” Uh oh.

Kelly Severide (Taylor Kinney) is not exactly thrilled. “There's something wrong with the new boss.”

In the footage from season 10 of Chicago MedSharon Goodwin (S. Epatha Merkerson), executive director of patient and medical services, explains, “We need to rethink the way this emergency department operates.”

In the next Med Scene: Dr. Dean Archer (Steven Weber) is not getting along well with his new employee Dr. Caitlin Lenox (Sarah Ramos). “How old are you?” Archer asks skeptically.

“How old are You?” Lenox snaps.

In the meantime, in the excerpts from season 12 of Chicago PoliceHank Voight (Jason Beghe) is apparently working himself to the bone after the incident in the season 11 finale that almost cost him his life.

“I'm from the police. I'm doing my job,” he emphasizes. When someone later points out that he “almost died in that basement,” he replies: “But that's not true. I'm still here.”

Although she is not seen in this first footage, Toya Turner will join the Intelligence Unit this season as Officer Kiana Cook, after Tracy Spiridakos left the role of Hailey Upton last season.

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Chicago Wednesdays starts September 25th on NBC with Chicago Med at 8 p.m. ET/PT, followed by Chicago Fire at 9 p.m. ET/PT and Chicago Police at 10:00 p.m. ET/PT.