Greg Mills

God Has Spoken. Cruz struggles with guilt over Flaco's death.

Dawson finds it hard to keep her emotions in check during an ambo run involving a pregnant teen. Elsewhere, the firehouse is called to the site of a building fire and Casey is forced to make a split-second decision when two victims are each need of life-saving assistance. In the aftermath, Casey is left to deal with the repercussions.

The team is on high alert when a previous incident during a fire call leaves a dangerous man on the loose with a vendetta to target Lt. Casey and Firehouse 51, and prompts CPD to step in. Dennis Mack, a buddy firefighter of Severide's father, comes to town to shadow the squad but may have ulterior motives.

Willis and Campbell travel to a Russian submarine to treat a sailor who has been wounded in an explosion; the staff at Angels Memorial treats violent criminals who got injured during a prison riot.

A citywide blackout during a code black leaves the staff in chaos; Elliot and Heather are trapped in an elevator with a woman in active labor; Willis and Dr. Nolan help a 92 year-old woman who thinks it's 1942.

After pulling a double shift, Mario risks his own life when he follows Willis to a construction site where two brothers are trapped on a crane 300 feet above the ground. Also, Leanne treats the wife of an orthopedist from Angels Memorial who is brought into the ER with mysterious injuries.