Steve Chikerotis

A familiar face returns to Firehouse 51 to serve with Kidd on a special task force. With Tony days away from breaking the CFD’s perfect attendance record, Mouch and Capp work to keep him safe. Old memories and grudges resurface when Gallo reunites with a family member.

Stella Kidd returns to Firehouse 51. The team must work together to put out a potassium fire in a tunnel.

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

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 finding her; Severide misunderstands his role as Cruz's best man; Mouch bites off more than he can chew.

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 idea for giving back to her community.

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.