[s8e4] Infection, Part I May 2026

is the fourth episode of Season 8 of the action-drama series Chicago Fire . It serves as the opening chapter of a massive three-part crossover event within the Chicago franchise, involving characters from Chicago Fire , Chicago Med , and Chicago P.D. . Crossover Viewing Order

Chicago Fire Season 8, Episode 4 – "Infection, Part I" . [S8E4] Infection, Part I

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 . is the fourth episode of Season 8 of

Watch the full series on Peacock or through Sky Go . Crossover Viewing Order Chicago Fire Season 8, Episode

Because this episode is part of a continuous storyline, you must watch the following episodes in order to see the full narrative: