Stephen Eugene Walker

Members of the firehouse are frustrated with their inability to help Chief Boden, whose job is on the line pending an internal investigation in the aftermath of a complicated call to a fire. Meanwhile, Lt. Severide struggles to accept his smaller role and adjusts to the presence of Capt. Patterson (guest star Brian White), his new commanding officer. Dawson shakes things up.

The pressure on Firehouse 51 is at an all-time high as the internal affairs investigation into the handling of a recent fire picks up steam. Just when it appears that game-changing evidence comes to light that would serve to bail out Chief Boden, new twists emerge that put his head right back on the chopping block.

Firehouse 51 rallies around Casey as a pregnancy complication leaves Dawson's life in the balance. After key arson files go missing, Severide starts to have suspicions about Nick. Acting truck lieutenant Herrmann keeps the house spirit on track be setting 51 with the task of getting Molly's reopened before Dawson is out of danger.