Karen Aldridge

Leaving the Station. A train accident leaves Mills doubtful about his future as a firefighter.

Soul Care. Dr. Rhodes begins his cardiothoracic surgery fellowship but gets off on the wrong foot with his new boss, Dr. Choi begins his life as chief resident, Sarah is caught off-guard by Dr. Charles, April tries to deal with her recently discovered illness.

A Dark Day. An explosion at a Chicago hospital rocks the city.

Out With a Bang. Casey forges ahead at the Firehouse despite signs that he may not be fully recovered from his harrowing accident.

Apologies Are Dangerous. Dawson begins a new chapter at Firehouse 51.

When an officer's body camera malfunctions during an altercation, Frank is faced with public backlash; Baez and Danny step in when a witness is denied protection by the U.S. Marshals Service; Erin looks into a rape claim made by a friend's daughter.