[s3e19] I Am The Apocalypse Apr 2026

A patient enters the ER claiming to carry a deadly airborne virus (revealed later as Marburg) and detonates a grenade .

(Oliver Platt): Chief of Psychiatry, whose first meeting with Chief Boden is a fan-favorite moment.

Hospital administrator Sharon Goodwin (S. Epatha Merkerson) places the facility under immediate quarantine, trapping members of 51 inside with a potential biohazard and an active electrical fire in the ceiling. [S3E19] I Am The Apocalypse

This episode introduced the core cast that would eventually lead Chicago Med :

Testing eventually proves the virus is not contagious, allowing the quarantine to be lifted. A patient enters the ER claiming to carry

Lieutenant Kelly Severide is critically injured in the blast while trying to stop the attacker. He spends much of the hour in surgery, experiencing visions of his late friend Shay while Dr. Hannah Tramble (Laurie Holden) fights to save him. Major Introductions & Arcs

(Laurie Holden): A skilled trauma surgeon. Aftermath & Relationship Beats He spends much of the hour in surgery,

Severide survives his surgeries but is shaken by the near-death experience.