Anthony Edwards Dr. Mark Greene Actor George Clooney Dr. Doug Ross Actor Eriq La Salle Dr. Peter Benton Actor Noah Wyle Dr. John Carter Actor Julianna Margulies Head Nurse Carol Hathaway Actor Gloria Reuben Jeanie Boulet Actor Laura Innes Dr. Kerry Weaver Actor Alex Kingston Dr. Elizabeth Corday Actor Maria Bello Dr. Anna Del Amico Actor John Aylward Guest Star Clancy Brown Guest Star Paul McCrane Robert Romano Guest Star George Eads Paramedic Greg Powell Guest Star Trevor Morgan Scott Anspaugh Guest Star Jonathan Scarfe Chase Carter Guest Star Michael Crichton Executive Producer John Wells Executive Producer