George Clooney, Julianna Margulies, and Eriq La Salle all reprise their roles of Dr. Doug Ross, Carol Hathaway, and Dr. Peter Benton, respectively. Clooney left in the Season 5 episode "The Storm (Part 2)" and returned for an uncredited cameo in the Season 6 episode "Such Sweet Sorrow." That episode also marked Margulies's last appearance as a series regular. La Salle left in the Season 8 episode "I'll Be Home for Christmas" and made brief appearances later that season in "It's All in Your Head" and "On The Beach." Like Anthony Edwards and Noah Wyle earlier this season, all three actors are listed in the opening credits as main stars rather than being billed as special guests or as making guest appearances.