[s8e4] Infection, Part I Apr 2026

As the medical crisis unfolds, the teams begin to suspect this isn't a natural occurrence.

The episode raises the stakes by placing the main characters in direct peril.

: Shortly after, Ambulance 61 discovers two more victims dead from the same infection in a private residence. [S8E4] Infection, Part I

The horror starts at a where several first responders are relaxing.

: While investigating a second lab assistant, Veronica Song, Detective Hailey Upton finds her collapsed and is accidentally covered in her blood. Upton is immediately placed in quarantine at Chicago Med to wait for test results. As the medical crisis unfolds, the teams begin

If you'd like, I can provide a summary of the conclusion in and Part III (Chicago P.D.) or dive deeper into:

The episode ends on a high-tension cliffhanger as the team realizes the perpetrator is still at large and has a broader, more deadly plan for the city. The horror starts at a where several first

: Investigations by the Office of Fire Investigation (OFI) confirm the university fire was deliberately set to destroy evidence in a lab that was actually researching treatments for this specific bacteria.