Lieutenant Severide is anxious to implicate the serial arsonist, while Dawson and Shay get a shock on a routine call. Meanwhile, suspicions continue to point to Clarke as the mole inside the firehouse and Molly's falls deeper into the red. Elsewhere, Mouch campaigns for union president, with the aid of Isabella, and Boden butts heads with Gail McLeod.
Elenco: Jesse Spencer , Taylor Kinney , David Eigenberg , Joe Minoso , Christian Stolte , Eamonn Walker , Yuriy Sardarov , Kara Killmer , Monica Raymund , Miranda Rae Mayo , Charlie Barnett , Lauren German , Annie Ilonzeh , Alberto Rosende , Dora Madison , Steven R. McQueen , Daniel Kyri , Hanako Greensmith .