'One Chicago' Crossover Event Finds [Spoiler] Caught in Life-Threatening Situation

The One Chicago NBC shows are airing on the same night for the first time ever, and they will be celebrating their new homes with a dramatic crossover event.

Chicago Med, Chicago Fire and Chicago P.D. will be airing the special hours for the second episodes of their upcoming seasons this fall, and there will be some changes in the schedule that day to accommodate for the episodes.

"Fire will come first, then Med, then P.D. We're starting the story in Fire," Chicago Med executive producer Diane Frolov told Us Weekly.

The crossover will kickstart with a large high-rise fire, according to executive producer Andrew Schneider, with the patients coming into the hospital causing everyone distress — but especially, Will and Jay Halstead.

"Their father is trapped in that building. During Med, we learn a lot about their relationship and past. Another firefighter also comes in with the patients at Med," Schneider told the outlet.

One of the firefighters will find themselves "in very serious condition." Chicago P.D.'s hour will delve into who caused the fire and why it happened.

"It's fantastic. I can tell you that it is very dramatic and action-packed and what happens in Fire is also very personal to some members of our universe," P.D. executive producer Rick Eid said.

Despite the big crossover happening in episode two, executive producers teased there will be One Chicago storylines overlapping through all three series all year.

"I've been wanting this for a while, I know Dick Wolf's been saying it since season 1. I am thrilled, especially since we can tie some stories together in ways that we've never been able to," Chicago Fire co-creator Derek Haas told the outlet.

All three Chicago series premiere Wednesday, Sept. 26 starting at 8 p.m. ET on NBC, which puts the One Chicago crossover event on the following week's schedule, airing on Oct. 3.

Of the three series, Chicago Fire is reportedly the lowest rated with an average of 6 million viewers and a 1.1 demo rating. Med wins with an audience of 6.7 million and a 1.2 rating. Chicago P.D. has 6.4 million in total viewers and a 1.2 rating.

The good thing with crossovers is seeing the casts of the shows come together for the special episodes, including Chicago Med stars Nick Gehlfuss, Yaya DaCosta, Colin Donnell, Brian Tee, Torrey DeVitto, and Oliver Platt; Chicago Fire's Jesse Spencer, Taylor Kinney, Eamonn Walker, Monica Raymund, and David Eigenberg; and Chicago P.D.'s Jason Beghe, Jon Seda, Jesse Lee Soffer, Patrick John Flueger, and Elias Koteas.

It is not yet known if all of the series' stars will make appearances in the epic event.