One Chicago crossover ratings are in, and the results will surprise you

The ratings continue to benefit one show in particular.

CHICAGO P.D. -- "In The Trenches: Part III" Episode 12014 -- Pictured: (l-r) Toya Turner as Kiana Cook, Taylor Kinney as Kelly Severide, Dermot Mulroney as Chief Dom Pascal -- (Photo by: Elizabeth Sisson/NBC)
CHICAGO P.D. -- "In The Trenches: Part III" Episode 12014 -- Pictured: (l-r) Toya Turner as Kiana Cook, Taylor Kinney as Kelly Severide, Dermot Mulroney as Chief Dom Pascal -- (Photo by: Elizabeth Sisson/NBC)

The One Chicago crossover was a success. It yielded some of the franchise's best ratings of the year, and did so for all three hours of its Wednesday night block. This was to be expected, of course. There wasn't anybody who was going to tune in for just one portion of the crossover event, given that it was crucial to watch all three to understand the plot.

That said, the ratings fluctuated depending on the episode. Chicago Fire, Chicago Med and Chicago PD drew different levels of interest according to Nielsen, and the results surprised. Chicago Fire is the most popular show in the franchise, historically, and it kicked off the crossover event in the slot that's usually reserved for Med.

Chicago Med led the charge with 6.6. million viewers

Chicago Med - Season 10
CHICAGO MED -- "In The Trenches: Part II" Episode 1011 -- Pictured: (l-r) Jessy Schram as Dr. Hannah Asher, Toya Turner as Kiana Cook -- (Photo by: George Burns Jr/NBC)

Chicago Fire's episode garnered 6.3 million viewers, which was actually the smallest of the entire night. It was still a season high, mind you. The same can be said for Chicago PD, which netted their most watched episode of the season with 6.4 million viewers according to TV Line.

These are excellent numbers, and an indicator that the One Chicago franchise is still going strong. The thing that most took us by surprise, though, is the fact that Chicago Med led the charge with an impressive 6.6 million viewers. It's the latest victory for a medical drama that has been killing it in the midst of its 10th season.

Chicago Med turned quite a few heads during the One Chicago fall finales. Fire proved to be the victor but Med was close behind with a 0.4 gap. It was the smallest viewership gap in a whopping 4 seasons, and it proved that Med was becoming one of the franchise's most valuable properties.

Chicago Fire and PD had season-high ratings

Chicago Fire - Season 13
CHICAGO FIRE -- "In The Trenches: Part I" Episode 13011 -- Pictured: Dermot Mulroney as Chief Dom Pascal -- (Photo by: Peter Gordon/NBC)

It would be easy to argue that the One Chicago viewership benefitted from fans tuning in once they realized a crossover was airing, but the decrease during Chicago PD indicates that Med was the title that intrigued fans the most.

What makes this spike even more interesting is that Med technically had less to do during the event than Fire or PD. There were a handful of characters who saved lives throughout the crossover, but in reality, Med's ensemble took a backseat to Fire and PD when it came to resolving the main conflict. It makes the show's popularity within the framework of the crossover even more impressive.

We wouldn't be surprised if Med managed to overtake Fire as the most popular One Chicago show by the end of the season.