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 Ken Kercheval Mr. Zwicki Guest Star Julie Bowen Roxanne Please Guest Star Vince Vieluf Bernard Gamely Guest Star Denise Dowse Mrs. Lysell Guest Star Chris Conner Mrs. Zwicki Guest Star Maricela Ochoa Mrs. Fernandez Guest Star Barbara Whinnery Mrs. Draper Guest Star Yvonne Zima Rachel Greene Guest Star Conni Marie Brazelton Nurse Connie Oligario Guest Star Laura Cerón Nurse Chuny Marquez Guest Star Michael Crichton Executive Producer John Wells Executive Producer