The One Chicago crossover is the first of its kind in five years and is a massive undertaking.

Despite occurring across the three shows, the showrunners say it feels like one continuous movie.

[It] really is different.

Sergeant Trudy Platt (Amy Morton) takes a call in ‘Chicago P.D.'

Image via NBC

It doesnt feel like three episodes,Chicago FireshowrunnerAndrea NewmantoldTVLine.

NBC gifted viewers with an early look at the event.

A sneak peek from the first part of “In the Trenches” showsChicago P.D.

Chicago Fire Movie Poster

Couples Are Tested During the One Chicago Crossover

The video above takes the viewerright into the action.

The explosion has already happened, and CFD is working hard to evacuate buildings.

While the situation is stable, things could escalate at any moment.

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The One Chicago crossoverwill put a lot of stress on couples.

The interaction between Mouch and Platt is just but one of those.

Moments like these expose the harsh realities of the job to couples.

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Tune in to NBC tonight, January 29 to watch all three parts of “In the Trenches.”

Chicago Fire

Chicago P.D.