Severide and Stella are on the lookout for a very unstable Grant, who left Chicago Med without notice. Now that Dawson is responsible for Louie, she questions her dangerous career path as a firefighter. Casey continues his work as Alderman but his relationship with his political consultant, Susan Weller, cools. Problems continue for Borrelli, who still blames Chief Boden for the death of his brother, and the situation reaches a boiling point. Meanwhile, Mouch and Brett start off on a new venture together.