Individual episodes are available for purchase on Apple TV and Amazon Prime Video .
Firehouse 51's first responders must work alongside the medical team at Gaffney Chicago Medical Center to contain the outbreak while the Intelligence Unit from Chicago P.D. investigates if the infection was spread intentionally .
You can find this episode and the rest of the crossover on major streaming platforms and digital stores:
Watch the full series on Peacock or through Sky Go .
Chicago Fire Season 8, Episode 4 – "Infection, Part I" .
As panic grows, the city's heroes face a race against time to identify the source of the bacteria before it becomes a full-blown epidemic. Where to Watch