Severide takes matters into his own hands as he works to implicate Hadley as the arsonist. Using his Find my Phone app, Severide follows Hadley to another dangerous building and catches him in the act. Finally putting an end to his serial arsons.
Shay and Dawson witness one of the regular nuisance callers take a gun and use it to kill himself. The act causes a rift to form between them.
Benny meets with Gail to talk about Boden.