The members of Firehouse 51 struggle to cope when one of their own dies in a fire, while lieutenants Casey and Severide blame each other for the tragedy.
Devon treats his first patient with a revolutionary medical fluid that doesn't go as planned; an overdosed John Doe is rushed to Chastain, leading Conrad straight into a much bigger scandal than he expected.
When Conrad confronts a pharmacy owner about fraudulent prescriptions being filled under his name, the situation takes a dangerous turn; the ER is sent into chaos when a street racing accident results in multiple severe injuries.
Conrad and Cade work with a Medicare patient who sheds some light on the inner workings of the prescription fraud situation; Leela works herself to the brink of exhaustion to avoid having a conversation with Devon.
While the group searches for something to advance their quest, one of them recalls their struggles in the early days of the apocalypse; a game of truth or dare brings emotions to the surface.