Caitlin Carver

Severide struggles with the cost of helping Det. Pryma with the Martucci case. Gallo campaigns for Herrmann to represent 51 at the National Firefighter’s Association’s Winter Conference. A familiar face makes a shocking return.

The big wedding day arrives and Firehouse 51 welcomes Casey back to celebrate the joyous occasion. Emma’s plans to replace Violet come to a shocking end.

Secretary of the Navy Sarah Porter's daughter is kidnapped; NCIS Special Agent Valerie Page, McGee's childhood friend, assists the team with advance tactics training.

Mouch and Ritter work together to solve a murder mystery. Severide and Cruz tackle a food truck fire. Gallo goes to see Hawkins about Violet.

A family friend asks Herrmann for some advice on opening a bar; tensions run high between Emma and Violet; Kidd struggles to keep her team together.

Det. Pryma’s case comes to an explosive end with Kidd and Carver’s lives in danger. Brett installs an infant Safe Surrender Box at 51. Violet is determined to take Emma down.