Anthony Ferraris

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.

Severide and Kidd continue to investigate Benny's old arson case, unexpected news leads Brett to ponder a big decision and all hell breaks loose.

Kidd and Severide's honeymoon is interrupted by a dangerous person from their past. Kidd's former academy classmate joins Firehouse 51. Brett and Violet reflect on their relationships.

Javi spends a couple of shifts at Firehouse 51. Kidd and Carver work together to help Carver's former boss. As Hawkins and Violet's relationship blossoms, Gallo turns his attention elsewhere.

A major security breach in the city's computer networks forces Firehouse 51's senior leaders to take matters into their own hands; Severide gears up for an arson investigation.

A rare but deadly bacteria takes its toll on numerous victims around the city, leaving Chicago's finest first responders to work together alongside the CDC to resolve the dangerous situation. Severide suspects something bigger is happening.