When a high school student becomes an innocent victim of a gang retribution incident, a very determined Lt. Casey tries all means necessary to resolve the issue. Severide lends a hand to Detective Holloway, who is working a dangerous undercover investigation, and watches over her 9-year-old son at the firehouse. Brett and Jimmie are called to aid a woman who takes a fond liking to Jimmy. Meanwhile, Otis makes a surprising discovery that leaves him very concerned and Herrmann goes toe-to-toe with Stella to claim bragging rights over who can best run a bar.
No job is more stressful, dangerous or exhilarating than those of the Firefighters, Rescue Squad and Paramedics of Chicago Firehouse 51. These are the courageous men and women who forge headfirst into danger when everyone else is running the other way. But the enormous responsibilities of the job also take a personal toll.
With big reputations and hefty egos, the pressure to perform and make split-second decisions is bound to put squad members at odds. When a tragedy claims one of their own, there's plenty of guilt and blame to go around. In the middle of a divorce, Lt. Matthew Casey tries to go about business as usual, but can't help butting heads with the brash Lt. Kelly Severide of the Rescue Squad - and each blames the other for their fallen team member. When it's "go-time", though, they put their differences aside and put everything on the line for each other. This is a look inside one of America's noblest professions.