Daniel Kyri

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

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.

Tension builds when a group of rabble-rousers attempts 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.

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 at the Firefighting Expo; Commissioner Grissom returns.

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.

Casey further investigates a motorcycle accident at the request of the victim's son; Kidd, Foster and Brett bond while helping Kidd fix a mistake; Mouch and Otis have a falling out after Otis' teasing hits a sore spot.