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 Gray Powell Dr. Noah Wolf Guest Star Alex Spencer Emily's Dad Guest Star Robert Ifedi Biker Guest Star John Thomas Gauthier Billy 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, Director Melissa Aouate Executive Producer Henrik Bastin Executive Producer Andy Serkis Executive Producer Jonathan Cavendish Executive Producer Will Tennant Executive Producer Arika Lisanne Mittman Writer