George Clooney and Julianna Margulies to Return to "ER"

ER, an NBC mainstay for 15 years, will end its run on April 2, but not before two of the cornerstone characters of the show's early years make a return appearance.

BuddyTV.com is reporting that George Clooney, who played pediatrician Dr. Doug Ross, and Julianna Margulies, who played Nurse Carol Hathaway, are filming scenes this week on a closed set. Although both have made previous statements denying this claim, TVGuide.com reports that sources have said both will return for one more episode.

Their characters' on again/off again relationship helped fuel the early success of the show. In the pilot episode, Nurse Hathaway was admitted into her own ER for an attempted suicide that was the result of another breakup with Dr. Ross.

Clooney left the show in 1999 after a five-year stint when his character, Dr. Ross, moved from Chicago to Seattle. Margulies's Nurse Hathaway left the following year with their twins to reunite with Ross.