The horror starts at a where several first responders are relaxing.
: Additional cases surface, including a woman and her child at a gas station, leading the CDC to step in as the situation escalates into a full-scale city epidemic. Investigation and Suspicion
: Firehouse 51 responds to a major fire at Central Chicago University . While inside, Kelly Severide notices a laboratory wall bearing the same "BRT" initials the original victim mentioned.
: The original victim, Stuart Anderson, is identified as a lab assistant who had previously made threats via email, suggesting a bioterrorist plot. Personal Stakes and Danger
( S8E4 ) serves as the explosive opening to a massive three-part One Chicago crossover event, weaving together the worlds of Chicago Fire , Chicago Med , and Chicago P.D. .
: A man named Stuart Anderson suddenly collapses, revealing a gruesome infection on his leg while chanting the letters "BRT" .
As the medical crisis unfolds, the teams begin to suspect this isn't a natural occurrence.
If you'd like, I can provide a summary of the conclusion in and Part III (Chicago P.D.) or dive deeper into: