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…

Det. Pryma asks for Severide’s help on a case involving explosives. Gallo and Carver clash after Gallo improvises on a call. Violet encourages Brett to start dating again.

Firehouse 51 must band together when one of their own is taken hostage.

Firehouse 51 must band together when one of their own is taken hostage.

Severide and Herrmann clash over office space. Boden looks at Pelham’s past as he considers making him permanent. Gallo’s resentment of Pelham comes to a head. Brett and Ritter force…

A call to a familiar location brings back mixed emotions for Severide. Herrmann heads out for a vacation. Casey is not thrilled with his replacement.

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…

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…

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…

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…

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…

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…

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…

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…

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…

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…

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…

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…

Severide must make a tough decision about the future of his career at Firehouse 51. Herrmann deals with the consequences of his temper. Cruz is excited to demonstrate the Slamigan…

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…

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.

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…

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….

Lt. 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…

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.

Severide gets angry at Cruz when he feels his orders were disobeyed in the field. Boden reconnects with an old high school friend during a call to a house fire….

Firehouse 51 is called in to battle a dangerous structure fire that places everyone in peril. Severide makes a big personal realization. Casey lends another helping hand to Naomi, the…

When the FBI takes over Firehouse 51 for an undercover mission, Casey and Severide volunteer to assist with the investigation. Kidd attempts to help Severide come to terms with recent…

After saving a young girl, Dawson is forced to make a tough decision when she finds out the girl’s father is addicted to painkillers. Herrmann loses his cool and gets…

Casey discovers a new crack house on the block that is harboring a female junkie. Dawson and Brett get assigned a new trainee for the shift. Meanwhile, Severide gets an…

Lt. Casey and Dawson apply for permanent adoption of Louie, but quickly discover a hurdle. Firefighter-turned-medical student Jeff Clarke approaches Lt. Severide with an interesting proposition. With hopes of reinvigorating…

Sylvie witnesses a murder and is threatened by the shooter not to go to the police. Firehouse 51 jumps into action when a fire breaks out at a restaurant and…

Boden believes Maddox is behind Serena’s accusations. Severide reaches out to Jamie, who’s Maddox’s lawyer, in an attempt to help. Patterson questions whether Boden can remain chief. Brett and Chili…

Herrmann tries to rescue a toddler from a structure fire. Mills discovers unexpected news.

The members of the firehouse spring into action when a helicopter explodes over a populated area.

Lt. Severide sticks his neck out for Dave Bloom, a fellow firefighter from Denver who is troubled by addiction. Elsewhere, Dawson and Shay leave town for a “girl’s weekend” at…

When the shooting of a young girl happens in their neighborhood, Cruz and his brother, Leon are forced to think about the gang they have tried to escape. The battle…

With tensions still running high between Chief Boden and Bennie Severide, things boil over when Mills confronts Bennie about the fire that killed his father. Meanwhile, Severide, Casey and Bennie…

At the site of a train accident, Peter Mills becomes deeply upset when he observes the dead body of a young victim. Unable to shake his emotional distress about the…

In the aftermath of Halstead’s apartment fire, Marcel, Choi and Archer work together to try to save the survivors; Charles and Med’s new fellow, Cuevas, help a paranoid patient; Scott…