Mark-Paul Gosselaar Brad Wolgast Actor Saniyya Sidney Amy Bellafonte Actor Jamie McShane Tim Fanning Actor Caroline Chikezie Major Nichole Sykes Actor Emmanuelle Chriqui Dr. Lila Kyle Actor Brianne Howey Shauna Babcock Actor McKinley Belcher III Anthony Carter Actor Henry Ian Cusick Dr. Jonas Lear Actor Vincent Piazza Clark Richards Actor Alain Uy Dr. Pet Guest Star Jason Fuchs Grey Guest Star Kecia Lewis-Evans Lacey Antoine Guest Star Adam Aalderks Paulson Guest Star Brooke Langton Valerie Guest Star Michael Reilly Burke Danny Guest Star Trieste Kelly Dunn Sierra Thompson Guest Star Julia Vasi Nikki Guest Star Matt Reeves Executive Producer Adam Kassan Executive Producer Ridley Scott Executive Producer David W. Zucker Executive Producer Liz Heldens Executive Producer Marcos Siega Executive Producer Jason Ensler Executive Producer