Casey heads to a local warehouse to conduct an inspection, where a forklift runs into a chemical tank and causes a massive acid spill that kills one employee. He takes shelter in the warehouse's break room with the surviving employee and the man's teenage daughter, but then discovers that no one actually called 911 so they're on their own to make it out alive.
He tries to open an air vent to the adjoining office but finds that the fumes have already spread - including toward piles of aluminum shavings, which would cause a massive explosion. Eventually he's able to break down another wall and send the daughter through to get help, bringing everyone to the warehouse to rescue them.
Dawson and Brett are brought to the residence of an elderly woman whose "senior advocate" wants to interject her opinion into the situation. But when they get a second call in the same day, they override the advocate and her supervisor in order to get the patient quicker help at Chicago Med. That lands them in hot water with Hatcher, and causes tension between Dawson and Brett, who tells her new partner not to put her in that position again.
Meanwhile, Mouch and Brett meet with a publisher interested in their book if they're willing to pay him to take it, and Otis reveals that he's been short-listed for a potential mission to Mars.