Show vet to appear on tonight's episode

George Clooney is set to make his return to “ER” tonight.

After much publicity about coming back to the show that made him a television star, Clooney will return in Thursday’s episode, titled “Old Times.” According to sources, however, he won’t be roaming the halls at County General.

Clooney spent five seasons on “ER” as pediatrician Dr. Doug Ross, with his character resigning and heading to Seattle. Former cast members Eriq LaSalle and Juliana Margulies, whose character dated Ross, will also appear in the episode.

Noah Wyle, who appeared in more than 250 episodes of the medical series, is currently in a story arc in which he’s trying to obtain a new kidney.

“ER” ends its 15-year run on April 2. NBC will air an hourlong retrospective that night, along with a two-hour series finale.

Neither Warner Bros. nor NBC would confirm Clooney’s appearance.

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