Zachary Quinto Dr. Oliver Wolf Actor Tamberla Perry Dr. Carol Pierce Actor Ashleigh LaThrop Dr. Ericka Kinney Actor Alex MacNicoll Dr. Van Markus Actor Aury Krebs Dr. Dana Dang Actor Spence Moore II Dr. Jacob Nash Actor Teddy Sears Dr. Josh Nichols Actor Donna Murphy Dr. Muriel Landon Actor Jane Krakowski Arianna Burnett Guest Star Dorrett White Nurse Estelle Carter Guest Star David Thompson Billy Guest Star Sanjay Talwar Jonah Guest Star Derek Johns Otto Guest Star Michael Grassi Executive Producer Greg Berlanti Executive Producer Sarah Schechter Executive Producer Leigh London Redman Executive Producer Lee Toland Krieger Executive Producer DeMane Davis Executive Producer Melissa Aouate Executive Producer Henrik Bastin Executive Producer Andy Serkis Executive Producer Jonathan Cavendish Executive Producer Will Tennant Executive Producer Sudz Sutherland Director Ryan McGarry Writer William Yu Writer