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 Kellie Martin Lucy Knight Actor Phyllis Frelich Dr. Lisa Parks Guest Star Harvey Korman Stan Levy Guest Star Chad Donella Kevin Delaney Guest Star Julie Bowen Roxanne Please Guest Star Christopher Holloway Kate's Dad Guest Star Cress Williams Officer Reggie Moore Guest Star Jon Sklaroff Eddie Hainey Guest Star Silas Weir Mitchell Marcus Hainey Guest Star Rhonda Stubbins White Mrs. Enloe Guest Star John Aylward Guest Star Michael Crichton Executive Producer John Wells Executive Producer