Iris is alarmed by Barry's disappearance and Cecile assures her everything will be OK; Team Flash is affected by a mysterious substance; Khione develops a better understanding of what she can and cannot control.
Stars: Grant Gustin, Candice Patton, Danielle Panabaker
Director(s): Kayla Compton
Writer(s): Greg Berlanti, Andrew Kreisberg, Geoff Johns