Sacred Ground September 25, 2019

The mattress factory fire spirals out of control. Truck and squad lay it on the line in hopes of getting the trapped victims out alive.

A Real Shot in the Arm October 2, 2019

Captain Casey struggles to get Chief Boden to sign off on an energetic new recruit. Against her better judgment, Foster extends an olive branch to her irritating new medic. Otis inspires Herrmann to seek new partners at Molly's. Brett realizes life in Fowlerton will take some getting used to.

Badlands October 9, 2019

Brett and Foster question the suspicious circumstances surrounding a brutal attack at a juvenile detention center, which leaves them searching for the truth. A convoluted new technology installed inside Firehouse 51 tests everybody's patience. Kidd gets chosen to represent the district at a leadership conference.

Infection, Part I October 16, 2019

A rare but deadly bacteria takes its toll on numerous victims around the city, leaving Chicago's finest first responders to work together alongside the CDC to resolve the dangerous situation. Following a fire at a local university that ties into the outbreak, Severide has suspicions that something bigger is happening.Part II continues on Chicago Med, Part III on Chicago PD.

Buckle Up October 23, 2019

Kidd must prove herself at the National Firefighter Leadership Conference while the rest of Firehouse 51 is called to two eerily similar car wrecks. Mouch tries to keep everyone in the firehouse informed by starting a newsletter, but things quickly get out of hand. Cruz deals with a heartbreak.

What Went Wrong October 30, 2019

Cruz and Severide suspect foul play when a fire started by an elderly woman turns deadly. Kidd, Foster and Brett create a women's-only lounge. Firehouse 51 celebrates some good news.

Welcome to Crazytown November 6, 2019

Severide must make a tough decision about the future of his career at Firehouse 51. Herrmann deals with the consequences of his temper after a run-in with a Chicago police officer. Cruz is excited to demonstrate the Slamigan at the Firefighting Expo. Commissioner Grissom returns.

Seeing Is Believing November 13, 2019

Severide begins his assignment at the Office of Fire Investigation and gets off on the wrong foot when, despite his orders, he reopens an old case. When the cause of an apartment fire hits close to home, Herrmann is on a mission to get to the bottom of it. Kidd finds herself burning the candle at both ends.

Best Friend Magic November 20, 2019

An unexpected visit throws Casey for a loop. Severide sets out to exonerate a wrongly convicted arsonist. Kidd pays the price for burning the candle at both ends. Cruz goes on a mission to fix one of Otis's old toys.

Hold Our Ground January 8, 2020

Members of Firehouse 51 are dismayed to learn their boundaries have been redrawn to overlap with an adjacent station and problems quickly arise. Casey and Gallo hunt a missing piece of equipment. Brett and Foster find themselves at odds. Mouch tries the find the recipient of a mysterious letter he discovers.

Where We End Up January 15, 2020

A pest control problem forces the 51 team to temporarily bunk with Firehouse 20. All under the same roof, Casey clashes with Capt. Delaney while Foster, Kidd and Brett fear Capt. Leone has it out for them. Boden mulls a procedural overhaul.

Then Nick Porter Happened January 22, 2020

A series of false alarms at a private school hinders the firehouse's ability to respond to legitimate emergency calls. Kidd asks for ideas to surprise Severide on his birthday. Cruz and Brett rent out their extra room, but the new tenant is more than they bargained for.

A Chicago Welcome February 5, 2020

The surprising arrival of a new fire truck brings both joy and chaos to members of Firehouse 51. Boden and Severide are asked to make peace with an old foe for the greater good. Brett receives family news while Foster plans a party with friends.

Shut It Down February 12, 2020

A series of mysterious gas leaks has members of Firehouse 51 puzzled and spread thin. Brett's conflicted when her birth mother gets serious about tracking her down. Severide misunderstands his role as Cruz's best man. Mouch bites off more than he can chew.

Off the Grid February 26, 2020

A series of teen opioid overdoses sees Severide partner with Sean Roman, but begins to suspect there's more to the story than his old friend is telling him. Casey tries to be there for Brett as she considers her birth mother's offer to meet.Part 1 of Crossover with Chicago P.D.

The Tendency of a Drowning Victim March 4, 2020

Boden is on edge after starting a new fad diet. Casey and Severide disagree on a call. Brett's birth mother shares life-altering news. A familiar face has a proposition for Herrmann.

Protect a Child March 18, 2020

Things get personal for Casey and Gallo in the aftermath of a suburban house fire involving a mother and her young son. Herrmann campaigns for more respect. Kidd has an idea for giving back to her community.

I'll Cover You March 25, 2020

Lt. Severide teams up with Seager and the OFI when a motel structure fire turns suspicious. Firehouse 51 members become amateur sleuths following a Reddit post involving one of their own. Brett continues to get invested in her birth mother, Julie.

Light Things Up April 8, 2020

Tension builds when a group of rabble-rousers attempt to lock down the firehouse. Brett is faced with a monumental decision. Cruz readies himself for a big day. Gallo and Ritter attempt to launch Firehouse 51 into the social media age.

51's Original Bell April 15, 2020

When one of 51's own gets injured on a call, Lt. Severide becomes obsessed with helping out. Foster contemplates a big decision. Kidd is concerned for one of her high school trainees.