Caitlin Carver

Leslie tries to complete some of her biggest city council goals, like hosting an NFL Play 60 event with the Indianapolis Colts, and trying to add fluoride to Pawnee's drinking water.

Leslie fights with Ben over questionable sales techniques at the local farmers market.

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.

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.

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.

Firehouse 51 prepares for their semi-annual firehouse inspection. Brett fights to save her paramedicine programme. Commander Martin Pearce asks Severide for a favour.