Photo: Yu Tsai

julianna marguiles

Julianna Margulieshad no idea just how much her life would change after being cast in NBC’s hit medical dramaERin 1994.

Margulies, who went on to play nurse Carol Hathaway for six seasons, still vividly recalls shooting the pilot episode. “I was supposed to die,” she tells PEOPLE in this week’s issue. “I was just a guest star. I had to drive my cranky little rental car to Crenshaw at this abandoned hospital.”

Detailing her tumultuous childhood and journey to Hollywood in her new memoir,Sunshine Girl: An Unexpected Life,the actress, 54, who married attorney Keith Lieberthal, 48, in 2007, also remembers meeting one very handsome costar that day in the makeup trailer. “And he could not have been kinder or sweeter,” she says.

For more from Julianna Margulies, pick up the latest issue of PEOPLE, on newsstands Friday, or subscribehere.

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juliana marguiles

Margulies also insists Clooney, 59, became her “mentor” during the production. “I followed and watched how he conducted himself on the set. When you create an environment that people feel safe in, then you do your best work. And George taught me that,” she says. “I felt so safe with him. I mean, I never thought, ‘Well, why would I be in the bathtub and he’s coming in?’ I was like, ‘Okay, I’ll be in the bathtub. Yeah, great.'”

Ballantine Books

SUNSHINE GIRL

Fans will finally get to see Margulies and Clooney together again — along withGloria Reuben, Noah Wyle, Laura Innes, Anthony Edwards and more — on Thursday,during a liveERcast virtual reunionon the daily seriesStars in the House, which will stream exclusively on PEOPLE’s social platforms.

Airing on Earth Day, the special episode will be held in benefit of theWaterkeeper Alliance— the fastest growing global nonprofit focused solely on clean water.

“I think I’m just as excited as the fans are to see them all,” says Margulies of the reunion, noting she regularly keeps in touch with Wyle, Clooney andEriq La Salleas well. “In fact, I literally just was emailing with George because I said, ‘I’ve written this book and you’re in it, and it’s not a tell-all, it’s just that I have to give credit where credit is due and you should have it. And where do I send it, under what name and what country?'”

Cast ofER.Sven Arnstein/NBCU

ER

The actress also sent copies to Wyle and La Salle. “I just said, ‘Listen, you guys are part of this trajectory of this incredible life, and you’re my history and so I’d like to send you the book,” she says.

Margulies’ memoir,Sunshine Girl: An Unexpected Life, will be released on May 4.

source: people.com