Episode 1 | Let It Burn

Casey finds himself in dangerous territory at the center of an undercover operation to bring down a trafficking ring out of Nesbitt's strip club.

Episode 2 | A Taste of Panama City

Internal Affairs investigates Firehouse 51 following a complicated call to a fire.

Episode 3 | I Walk Away

Boden's job is on the line as the crew of Firehouse 51 continues to search for evidence that could clear him of any wrongdoing.

Episode 4 | Your Day Is Coming

A member of Firehouse 51 requires the support of the whole team to recover from a near disaster.

Episode 5 | Regarding This Wedding

Boden offers to host a wedding at the firehouse after a fire ruins the ceremony, but Chief Riddle is against it and his political aspirations cause friction among the firefighters.

Episode 6 | 2112

Severide and Patterson's differences reach a boiling point, while a visitor from Cruz's past asks for a favor.

Episode 7 | Sharp Elbows

Boden finds himself in the middle of a fiasco concerning a female neighbor he believes is setting him up.

Episode 8 | When Tortoises Fly

Patterson confronts Boden about his ability to lead the firehouse.

Episode 9 | Short and Fat

Clues to Serena's possible whereabouts are uncovered, while Captain Patterson has news for everyone.

Episode 10 | The Beating Heart

While a member of Firehouse 51 falls victim to a near-fatal stabbing, the other firefighters rescue a woman who attempted to commit suicide.

Episode 11 | The Path of Destruction

The city of Chicago braces for a tornado.

Episode 12 | Not Everyone Makes It

A tormented Herrmann is forced to make a difficult decision and Casey does his best to keep a shelter open that's housing recent tornado victims.

Episode 13 | The Sky Is Falling

Mysterious threats begin to emerge throughout Chicago and the situation gets worse when news of a mass shooting brings Firehouse 51 into a dangerous scene.

Episode 14 | All Hard Parts

Severide confronts Chili about her behavior, while Jimmy faces Antonio in the first annual "Battle of the Badges".

Episode 15 | Bad for the Soul

Severide and Cruz take matters into their own hands when Firehouse 51 responds to a suspicious call from a neighboring firehouse.

Episode 16 | Two Ts

A citywide propaganda attack against Casey's run for alderman makes him reconsider his candidacy.

Episode 17 | What Happened to Courtney

Severide and Cruz discover the remains of a case that may be connected to a case Severide worked on years ago.

Episode 18 | On the Warpath

Sylvie is threatened when she witnesses a murder.

Episode 19 | I Will Be Walking

Casey tries to use his political influence when a high school student is almost killed by a street gang.

Episode 20 | The Last One for Mom

Severide watches over Detective Holloway's son while she testifies in court as part of an undercover operation, but he's left to deal with the situation due to an unexpected turn of events.

Episode 21 | Kind of a Crazy Idea

Dawson risks her life to save a young boy from an apartment fire.

Episode 22 | Where the Collapse Started

Firehouse 51 heads to the scene of a building collapse where dozens of lives are on the line.

Episode 23 | Superhero

Dawson hopes to foster Louie while a dangerous structure fire puts a member of Firehouse 51 in a dangerous situation.