Julianna Margulies says her anger and George Clooney saved her 'ER' role

George Clooney really is a life saver.

Julianna Margulies recently shared how Clooney saved her ER character from a planned pilot episode death, but if it weren't for her getting "pissed" during her audition, she'd never have made it onto the series at all. "What happened was, I was in L.A. visiting a boyfriend," Margulies said on Friday's episode of The Kelly Clarkson Show . "I had three auditions that day, and being that I grew up with a hippie, crazy, wonderful mother, who was always late... I'm usually early, because I never want to keep anyone waiting."

But when she got to the audition, "there was probably 50 people in the waiting room and they were running two hours behind, and I was pissed." As Margulies began to storm out, "the casting director called my name and I rolled my eyes like, 'Oh really'... So I went in to audition for a recurring character, but I was so pissed off that I did it really rudely, a little New York anger. I knew I'd flunked, and I walked out of the audition, and the casting director said, 'Hold on a minute, you're not right for that part,' and I was like, 'Ya think?' But they said, 'You might be right for this head nurse, Carol Hathaway, but she dies in the pilot. Could you come and read for that?' So I went back in and I read for Hathaway with a lot of attitude. And I got the role!"

The audience applauded the amazing turn of events, but of course, that's only half the story. Host Kelly Clarkson asked the natural follow-up question: "She was gonna die? you were supposed to die?"

Three decades in retrospect, ER is unimaginable without Margulies' Carol Hathaway. She was the primary love interest for Clooney's Dr. Doug Ross, and the driving force behind many of most consequential storylines in the medical drama's first six seasons. But, Margulies revealed, "the character dies in the pilot from a drug overdose." Not in an early draft of the pilot — the actual pilot that aired on Sept. 19, 1994.

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"But the way the director [Rob Holcomb] shot it," Margulies explained, "he did it through George Clooney's eyes, because they had been an old flame. They did it through his eyes, so suddenly her death seemed really important to the audience watching for him that she not die. So I guess they do test audiences, and when the character died the whole audience went, 'Nooo!' Because they loved George Clooney so much, who doesn't."

Another "confluence of events" ran in Margulies favor when "Sherry Stringfield, who was one of the doctors in the operating... when I get brought in on the gurney, she for some reason [put] her clipboard to her mouth when she said, 'She's braindead.' So you don't see it! They just looped different lines in saying 'she's gonna be okay' or whatever, and they brought me back to life."

Margulies departed ER in 2000 after six seasons, and Clooney only stayed on for five, returning as a surprise guest on the season six finale. Doug and Carol parted ways at the end of season 5. Afterwards, Carol discovered she was pregnant with his child. The character largely stays out of any further romantic entanglements on her final season, opting to focus on raising their child. She's as shocked by Doug's presence at her Seattle home at seasons's end as the rest of the country was.

Margulies recently recalled , "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."

And it would have never happened if Margulies hadn't been so pissed off during her audition, nor if America hadn't loved George Clooney so much.