Anthony Edwards Dr. Mark Greene Actor George Clooney Dr. Doug Ross Actor Sherry Stringfield Dr. Susan Lewis Actor Eriq La Salle Dr. Peter Benton Actor Noah Wyle Dr. John Carter Actor Julianna Margulies Head Nurse Carol Hathaway Actor Rosemary Clooney Mary Cavanaugh, 'Madame X' Guest Star Byron Stewart Mr. Layton Guest Star Ping Wu Mr. Cheung Guest Star Joseph Ung Frank Cheung Guest Star Liz Vassey Liz Guest Star Rick Rossovich Dr. John 'Tag' Taglieri Guest Star Sam Anderson Dr. Jack Kayson Guest Star Anne Haney Mrs. Packer Guest Star Scott Jaeck Dr. Steven Flint Guest Star Conni Marie Brazelton Nurse Connie Oligario Guest Star