A new chief shakes things up at Firehouse 51. Violet and Novak work to uncover the truth behind a car crash. Cruz keeps a watchful eye on Severide and Damon's growing bond.
After Damon disobeys Kidd's orders in a call, he turns to Severide to protect him. Hermann searches for the perfect scent to spice things up with Cindy.
Violet risks her job to deliver a baby on a tragic call; Mouch, Capp and Tony help Cruz track down Javi's stolen bike; Damon's departure weighs on Severide.
Kidd and Severide investigate a trucking company responsible for a string of accidents; Herrmann recruits Kylie to help get new radios; Firehouse 51 celebrates Violet's birthday; Carver's allegiances are torn.
State Police impede Severide's investigation of a suspicious fire at a storage facility that uncovered ghost guns, Carver is back on thin ice with Kidd and Mouch has a winged nemesis at the station.
Pascal and Severide revisit a storage facility fire searching for new evidence. Cruz aids Mouch's exam preparation. Novak proposes a whole blood program to Chief Robinson.
The team responds to a crisis at a community center. Severide is forced to investigate one of his own squad members. Kidd helps a teacher going through a post-incident spin-out.
Chicago's first responders unite in the wake of a catastrophic gas explosion and fire that threaten a city government building. Herrmann reluctantly shadows Pascal while Violet, Novak and Dr. Frost take charge of triage efforts on site.
Herrmann investigates the rise in missing fire hydrants and teams up with Kylie to track them down. Kidd's cousin comes to town, revealing surprising family history. Violet and Novak treat the victim of a birthday cake smash gone awry.
After a daring rescue at an adventure park, Kidd asks Severide to create a ropes course for Girls on Fire; Violet's former nemesis returns, pleading for her help; Herrmann creates a signature cocktail for Molly's.
A surprise visitor from Novak's past joins Ambo for a late-night ride-along; Herrmann faces a mountain of Chief-level training records and incident reports; Violet catches Carver in a lie.
