It's all hands on deck when Firehouse 51 races to the scene ofa deadly chemical leak inside an industrial building. Withsquad and truck tested like never before, scores of workersare rescued but many are experiencing respiratory distress.This prompts truck 81, squad 3 and ambulance 61 to spring intoaction to transport the victims to nearby Chicago Med. Thesituation takes a turn from bad to worse in the midst of thechaos when a "patient" planted inside the hospitalgoes on a suicide mission armed with a grenade and claiming tobe the carrier of a deadly airborne disease. Trying to stop themadman from engaging the explosive device, a member of thefirehouse team is severely wounded in the blast and left toface life-threatening injuries. With no other choice, ChicagoMed is forced into lockdown until doctors and the Hazmat teamcan determine the severity of the airborne virus.
