- Steven Weber (Dr. Dean Archer)
- Jessy Schram (Dr. Hannah Asher)
- Luke Mitchell (Dr. Mitchell 'Mitch' Ripley)
- Sarah Ramos (Dr. Caitlin Lenox)
- Darren Barnet (Dr. John Frost)
- S. Epatha Merkerson (Sharon Goodwin)
- Oliver Platt (Dr. Daniel Charles)
Episode: Extreme Measures
Air Date: 2016-10-20
Runtime: 42 min
A car accident that occurs at the Chicago Marathon leaves a victim in critical condition and tests the mettle of Dr. Halstead, April and her fourth-year medical resident brother Noah, who must perform a difficult procedure in the field. A mother brings in her 8-year-old girl experiencing a sudden hearing loss and Dr. Manning is left to tend to the case, which takes a complicated turn. Dr. Choi deals with Olga, a woman who is malnourished, prompting him to bring in Dr. Charles to help assess the case. Meanwhile, Goodwin takes measures to get her personal life in order.