Severide (Taylor Kinney) and Stella (Miranda Rae Mayo) are on the lookout for a very unstable Grant (guest star Guy Burnet), who left Chicago Med without notice. Now that Dawson (Monica Raymund) is responsible for Louie, she questions her dangerous career path as a firefighter. Casey (Jesse Spencer) continues his work as Alderman but his relationship with his political consultant, Susan Weller (guest star Lauren Stamile), cools. Problems continue for Borrelli (Steven R. McQueen), who still blames Chief Boden (Eamonn Walker) for the death of his brother, and the situation reaches a boiling point. Meanwhile, Mouch (Christian Stolte) and Brett (Kara Killmer) start off on a new venture together.