: Matthew Casey continues to hide the severity of his head injury and lingering headaches.

: Severide trains a group of recruits, including Jacob Mercer , whose father is a high-ranking CFD official and friend of Chief Boden.

: After a deli owner named Ronnie collapses twice, the pair uses Narcan and medical sleuthing to find the cause.

: They deduce Ronnie is being poisoned with muffins by his own wife. 3. Casey's Health Crisis

Fire 9x11: Chicago

: Matthew Casey continues to hide the severity of his head injury and lingering headaches.

: Severide trains a group of recruits, including Jacob Mercer , whose father is a high-ranking CFD official and friend of Chief Boden. Chicago Fire 9x11

: After a deli owner named Ronnie collapses twice, the pair uses Narcan and medical sleuthing to find the cause. : Matthew Casey continues to hide the severity

: They deduce Ronnie is being poisoned with muffins by his own wife. 3. Casey's Health Crisis including Jacob Mercer