The firehouse reacts to some exciting news, a mysterious stranger arrives and a shocking call takes Severide's breath away.
Dean and Ethan respond to a scene that brings back some bad memories. When Carol's condition worsens, Natalie is willing to do whatever it takes to get her mom feeling better.
Severide and Casey try to find the best fit for Kidd. Ritter, Gallo and Violet help plan an event for Mouch.
A fire breaks out at a pet food factory and Casey and Severide help the owner, Pete, get to the bottom of it. The annual garage sale takes place at 51 and everyone is on edge.
A mysterious caller who is in danger relies on Kidd to help save her and her brother. The firehouse helps Cruz get ready for fatherhood.