
As the firefighters, rescue squad and paramedics of Chicago Firehouse 51 forge headfirst into danger, the choices they make can mean the difference between life and death. But from the relentless pressure of saving lives, an extended family is forged. When it's go time, Firehouse 51 lays it all on the line for each other. This high-octane drama from Executive Producer Dick Wolf offers an edge-of-your-seat view into the lives of everyday heroes committed to one of America's noblest professions.

Evidence at a storage unit fire seems to be connected to the blaze that took Shay's life; Chaplain Orlovsky is in a car accident.

More clues emerge about the fire that killed Shay, leading Severide to a former nemesis; Shay's sister visits; Cruz is faced with a surprise; Boden tries to help his father.

The pursuit of a missing teenager leaves Mills and Brett stranded in unforgiving elements; members of the firehouse care for an abandoned newborn; Severide receives an intriguing proposal; Boden is at odds with his father (Richard Roundtree).

A temporary chief fills in for Boden, who is forced to take some time off for personal reasons; Lt. Severide deals with an unwelcome addition to the squad; Brett becomes close to a girl she previously rescued; Casey starts seeing a new woman.