How the One Chicago 'Infection' Crossover Incorporates Football

Ileane Rudolph
Preview Sandy Morris/NBC

To please the crossover-loving fans of producer Dick Wolf's trio of first-responder dramas, "we try to top ourselves each time," says Chicago Fire exec producer Derek Haas, quipping, "It's like at this point we do Fast & Furious 9 where the moon is crashing into the Earth!"

Wednesday's new effort (with Fire shifting to 8/7c) incorporates America's most popular sport: football. Wolf and Haas came up with a story about a deadly bacterial disease — and the outbreak starts at a Bears game when a tailgate partier collapses.  

The shows took over the massive Soldier Field parking lot, hired 500 extras, and gave cast members the burdensome tasks of tossing footballs and grilling sausages (in official team gear, thanks to the NFL's approval). Plus, says Haas, "On game night, they let us fly a helicopter [to shoot] over and around the stadium and then down toward the tailgating."

Once the party goes out of bounds, though, someone from P.D. ends up in quarantine. Firehouse 51 is called to a blaze at a university biology lab (hmm…), and Fire's Lt. Kelly Severide (Taylor Kinney, above right, with, clockwise from left, Miranda Rae Mayo, Marina Squerciati, Kara Killmer, and Med's Torrey DeVitto) suspects arson. That brings in P.D.'s Sgt. Hank Voight (Jason Beghe) and his Intelligence Unit.

12 Things We Learned From One Chicago's 'Apocalyptic' Crossover Trailer (PHOTOS)

12 Things We Learned From One Chicago's 'Apocalyptic' Crossover Trailer (PHOTOS)

'Fire,' 'Med,' and 'P.D.' are teaming up to tackle a citywide attack and one of their own may be infected!

Can they notch a win in this crisis?

Chicago Fire, Wednesday, 8/7c, NBC

Chicago Med, Wednesday, 9/8c, NBC

Chicago P.D.Wednesday, 10/9c, NBC