Goran Visnjic Dr. Luka Kovac Actor Maura Tierney Abby Lockhart Actor Mekhi Phifer Dr. Gregory Pratt Actor Parminder Nagra Dr. Neela Rasgotra Actor Linda Cardellini Nurse Samantha Taggart Actor Shane West Actor Scott Grimes Dr. Archie Morris Actor Laura Innes Dr. Kerry Weaver Actor John Stamos Dr. Tony Gates Actor Sally Field Maggie Wyczenski Guest Star Armand Assante Richard Elliot Guest Star John Aylward Dr. Donald Anspaugh Guest Star L. Scott Caldwell Dr. Rabb Guest Star Dahlia Salem Dr. Jessica Albright Guest Star Troy Evans Frank Martin Guest Star Yvette Freeman Nurse Haleh Adams Guest Star Kyle Richards Nurse Dori Guest Star Montae Russell Dwight Zadro Guest Star Dominic Janes Alex Taggart Guest Star Christopher Chulack Executive Producer Michael Crichton Executive Producer David Zabel Executive Producer John Wells Executive Producer R. Scott Gemmill Executive Producer