Chaon Cross

Following the gutsy firefighters, rescue squads and paramedics of Firehouse 51. No field is more dangerous yet so exhilarating, but the personal lives of these men and women provide close competition.

Darden's widow publicly blames Severide for her husband's death and Casey makes a decision about his future with Hallie.

Lt Severide is targeted by an arsonist, Battalion Chief Boden clashes with Gail McLeod the anniversary of Andy's death, Shay has suspicions, and Mari visits Mouch.

Severide is on edge after the arson attack, fearing what might be in store next. Shay and Dawson, meanwhile, plan to party away their problems.

With tensions still running high between Chief Boden and Bennie Severide, things boil over when Mills confronts Bennie about the fire that killed his father.

Severide tries to prove his suspicions about the arsonist's identity, Casey gets accustomed to his new lifestyle, and Dawson goes on a date with a regular from the bar.