Season 4 Episode 13
"The Sky Is Falling"
Chicago braces for a large-scale threat; Chili's alcoholic past causes a rift inside 51; Casey confronts a shady politician.
Several false-alarm terror threats place the firehouse, P.D. and Med on high alert; the FBI thinks this is a tactic by an unknown group to scatter citywide resources before a large-scale attack. The FBI's suspicions prove true when terrorists target a community center, taking the building hostage and killing several civilians. Through quick thinking and bravery, Severide (Taylor Kinney), Cruz (Joe Minoso), Brett (Kara Killmer) and others who are caught inside contain the situation with minimum casualties. Severide's love interest, an FBI agent, is shot in the attack, but survives. Even though their love must remain a secret, she tells Severide she will never forget him.
Casey (Jesse Spencer) investigates Alderman Becks, the politician who asked for Casey's help with the tornado relief efforts. The $50,000 that was raised is still unaccounted for - and Casey wants Becks to answer for its whereabouts. Even though Casey corners Becks, the answers are nowhere to be found.
Chili's (Dora Madison) erratic behavior is finally explained when it's revealed she was let go from her previous job for a drinking problem. Things turn heated when Chili requests that Brett be reassigned for insubordination - a request that Boden (Eamonn Walker) denies. In a mini-intervention between members of 51 and people from Chili's past, Chili is given a choice: change her ways and confront her problems or else.
A time-honored tradition is reinstated with the Battle of the Badges, a charity boxing event between the firehouse and P.D.'s District 21. With Borrelli (Steven R. McQueen) lacing up, and Herrmann (David Eigenberg) as his trainer, what could go wrong? A lot, it turns out, until former Golden Gloves boxer Dawson (Monica Raymund) steps in as trainer. In this corner: 51's Jimmy Borrelli. In the opposite corner: Officer Sean Roman (Brian Geraghty) for P.D. Place your bets!