A tornado threatens the city and Herrmann discovers the path may hit close to home. Chili and Brett lock heads when Chili makes a critical mistake that leaves a victim breathless, prompting Brett to report to Chief Boden regarding Chili's erratic behavior. Meanwhile, Otis pleads for Dawson to help him solve his women troubles and Severide is asked to lend assistance to agent Alex Ward from the Department of Homeland Security regarding a suspicious home.