There's a shift in show order for the crossover event. “Chicago Fire” will air first at 8 p.m., followed by “ Chicago Med “ at 9 p.m., with “ Chicago P.D .” concluding the event at 10 p.m.

6) Chicago Fire Season 8, Episode 4: "Infection: Part I" This trilogy continues in Chicago Med season 5, episode 4: "Infection: Part II" and concludes with Chicago P.D. season 7, episode 4 ...