Eriq La Salle, the fervent Dr. Peter Benton who has been on the show since its inception in 1994, will make his last appearance on Thursday night. The story will revolve around Benton's custody battle over his son. Resident pediatrician Dr. Cleo Finch, Benton's onscreen love interest played by Michael Michele, will also leave the show after a three-year stint.
As two of television's most prominent black actors, La Salle and Michele will undoubtedly leave a void behind. ER's executive producer John Wells called La Salle an integral part of the show's success and was disappointed when the actor decided to move on, Reuters reports.
In May, Anthony Edwards' character Dr. Mark Greene will be written off the series. Greene, the chief attending physician, will probably succumb to brain cancer, which he was diagnosed with last season.
Many people, however, agree that Edwards' character was played out. Green has gone through marital problems, emotional turmoil following a physical attack, the death of his parents, a battle with cancer and the difficulty of fatherhood.
Neither NBC nor the show's producers have commented on who would fill the latest vacancies at the fictional County General Hospital.
The departure of La Salle and Edwards leaves Noah Wyle, who plays Dr. John Carter, as the lone remaining star from the series' first episode. Their exits follows that of other high profile stars who have left the show in the past, including George Clooney, Julianna Margulies and Gloria Reuben. Sherry Stringfield and Ming-Na both left the show in its early stages but have since returned.
Robert Thomas, head of Syracuse University's Center for the Study of Popular Television, told Reuters that ER's revolving door of characters is like a series of life extending transplants that keep the show fresh.
"The only way you can keep from wearing out a drama like this is to keep replacing it, organ by organ, by organ," Thomas said. "It's defying age by reinventing itself, but never all at once. Do it all at once and you destroy the series."