Barry helps Raph investigate Sue Dearbon's disappearance hoping to get him back to Central City for a surprise. Nash recruits Allegra to help him, while Cecile gives Chester some advice.

While Bloodwork and Dark Flash infect Central City, Cisco tries to come up with a way to stop them. Joe is badly injured, and Iris has faith that the real Barry is still alive somewhere within the twisted monstrosity of the dark speedster.