George Clooney Recalls ‘Miracle’ of Realizing He Had Steady Work After “ER ”Smashed Ratings Expectations: ‘It Worked Out’

George Clooney is remembering the role that made him famous.

Clooney’s role as the hunky Dr. Doug Ross in the medical drama catapulted him to stardom — and solidified his Hollywood heartthrob status. He would go on to launch a prolific film career.

Speaking on the Friday, Dec. 5 episode of Live With Kelly & Mark, the 64-year-old actor said he remembered shooting the show’s pilot episode.

“It was a two-hour pilot,” Clooney said. “And I got to know all the people who ended up becoming very dear friends — Tony Edwards, Julianna Margulies, Noah Wyle … we all became a family.”

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He continued: “And then the show aired and at the time there were two hospital shows coming on Thursday night, at the same time. And one of them was Chicago Hope and one of them was ER. And Chicago Hope was supposed to kill us and we sort of doubled them, and overnight, there was that moment you realize … ‘I’ve got a job for a year. It’s like, a miracle. I’ve got a job for a year.’ And then, it worked out.”

ER debuted on NBC in 1994 and ran for 15 seasons, before ending in 2009. The groundbreaking medical drama, created by Michael Crichton, also starred Sherry Stringfield, Eriq La Salle and Noah Wyle.

Clooney left the show in 1999 at the end of season 5, but returned for cameos in season 6 and for the series finale.

In the years since, he has remained in touch with his former castmates.

In April, Clooney had a mini-ER reunion when he was photographed with Marguiles, Edwards and Wyle — a.k.a. Dr. Doug Ross, nurse Carol Hathaway, Dr. Mark Greene and Dr. John Carter — while the group celebrated the April opening night of Good Night, and Good Luck, the stage adaptation of the hit 2005 movie, in which Clooney starred.

And in October, Marguiles told PEOPLE that she had reached out to her former costar to give him “a lot of kudos” for his decision to do Broadway.

“I just emailed him and said, ‘I’m so proud of you. You don’t have to do this,’ ” she recalled.

Marguiles has also said the two still sign their personal emails to each other ‘Love, Carol’ or ‘Doug.’ ”