Steve Chikerotis

Kidd and the team embark on a mission to help Severide as he struggles to process his father Benny's death.

Stella Kidd returns to Firehouse 51; the team must work together to put out a potassium fire in a tunnel; after that incident, Ritter begins to worry about a young cop who witnessed the fiery death of a truck driver.

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.

Firehouse 51 is thrown into chaos due to a series of mysterious gas leaks. Meanwhile, Brett struggles with feelings about her birth mother. Severide misunderstands his role as Cruz's best man and Mouch bites off more than he can chew.

A suburban house fire involving a mother and son hits home for Casey and Gallo. Meanwhile, Kidd has a charitable idea to help give back to her community.

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