- 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: Natural History
Air Date: 2016-10-06
Runtime: 42 min
Dr. Manning and Jeff Clarke are forced to figure out a mystery illness when an Indonesian man who doesn't speak English arrives at the hospital in dire straights. Maggie takes Dr. Halstead to her family reunion. Dr. Rhodes takes on a complicated heart surgery without consulting Dr. Latham. Dr. Reese and Dr. Charles encounter a woman experiencing an unusual pregnancy.