ER Bringing Back Clooney with Margulies before Checking Out

The on-screen reunion that many felt needed to happen before ER 1-12 could properly end its 15-year-run will come to fruition after all.
Clooney last checked into ER 1-12 in May 2000, making an unbilled, end-of-episode appearance so as to properly usher off Margulies' nurse Hathaway. The secretly filmed scene had Carol approaching a dock, where Doug waited for her, smiling yet silent.
Indeed, Clooney's publicist as recently as September pulled a Debbie Downer by deflating talk of the movie star's possible drop-by, saying, "It is something he has already done."
Weeks later, Margulies herself scoffed at the idea of returning during ER 1-12 's final season, explaining, "I left Carol Hathaway in the best scenario possible. I can't imagine making it any better."
Already this season, Anthony Edwards reprised his role as Mark Greene (appearing in a "new" flashback with Laura Innes, aka Weaver); Alex Kingston put in an appearance as Mark's widow, Elizabeth, on Jan. 15; and Noah Wyle is due back as Carter for the final four episodes (though that could change in light of the extended order).
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