Julianna Margulies and George Clooney will forever be linked to their ER characters, a fact that doesn’t bother them in the slightest.

“It always had to be Carol and Doug, in the end,” Margulies recently told the Television Academy in an interview commemorating the series 30th anniversary. “George and I, to this day, still sign our personal emails to each other ‘Love, ‘Carol’ or ‘Doug.’”

Nurse Carol Hathaway and pediatrician Doug Ross remain one of the most cherished and iconic couples in small screen history. Margulies and Clooney’s characters parted ways in season 5 when Ross was forced to leave Cook County General Hospital for Seattle after a number of ethical breaches. But ER shocked everyone by reuniting the characters in the season 6 finale, which was also Margulies’ last episode.

The reunion had to be kept so secret that executive producer John Wells had to exclude it from the table read. When Margulies discovered that her final script “didn’t really have a farewell to Carol at all,” she “got very emotional,” fleeing to her trailer.

Wells met her there, where his consideration for her pain overwhelmed his desire to keep the Clooney’s surprise, one-episode return confined to as few people as possible. “‘Look, we have the right ending for Carol. But we can’t tell anyone. Because if it gets out, it won’t be a surprise,'” Margulies recalls him saying. She joked, “I wish he had warned me before I went into that table read!”

Margulies’ character Carol largely stayed out of other romantic entanglements in her final season, opting to spend time with her and Doug’s newborn twins. When she leaves Cook County General for Seattle to find Doug, audiences had no reason to suspect she’d find him. But find him she did, casually strolling up the length of a dock before taking her in his arms in one of the show’s defining shots.

“I remember my mom saying to me — she was so shocked because everyone knew George was off the show — my mother said she screamed, which I think was a lot of people’s reaction,” Margulies shared. “It was the right ending for them because Carol and Doug were destined to be together.”

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Margulies and Clooney’s characters returned one more time for the 2009 episode “Old Times,” but have reunited several times at subsequent ER reunions.

ER alum Mekhi Phifer presented an award at the 2024 Emmys as part of a tribute to TV doctors alongside Mindy Kaling (The Mindy Project) and Zach Braff (Scrubs). Margulies’ new series, The Morning Show, was up for 11 nominations at the ceremony and won one – Outstanding Supporting Actor in a Drama Series, which went to Billy Crudup.