George Clooney on Whether He'd Do an ER Reboot: 'It's Hard to Catch Lightning Again'

George Clooney is weighing on whether he'd join a reboot of ER, on which he starred as Doug Ross for 15 seasons.

Clooney, 59, opened up about the possibility of a reboot during a live virtual reunion of the ER cast on Stars in the House to support costar Gloria Reuben's organization, Waterkeeper Alliance. The nonprofit aims to ensure that communities globally have clean water.

The star said during the special Earth Day episode — which streamed exclusively on PEOPLE's social platforms — that he's not sure whether the magic of the original series, which ran from 1994 to 2009, would be able to be recaptured.

"I don't know. The hardest part is that when you look at the show and consistently over so many years — it would be hard to say that you could do it at the level that we did it," he said of a potential reboot. "I'm not sure that that's available."

The Ocean's Eleven star shared that he's been rewatching the show recently with his wife, Amal Clooney, calling the series "such great television."

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"This is better than anything I see in film or anywhere. This is stunning. It's stunning work," he said of the season 1 episode "Love's Labor Lost."

"I felt that way about a lot of episodes I watched," Clooney added. "I'm not sure [about a reboot]… it's hard to catch lightning again."

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"You can't capture lightning in a bottle twice," Julianna Margulies, who played Carol Hathaway, agreed. "I think you have to leave what was so beautiful and move on, because it just feels cheap… It would cheapen it for me."

While the cast seemed to generally agree that a reboot wouldn't be the same as the first go-around, Ming-Na Wen, who played Jing-Mei Chen, said she'd enjoy a reboot to reconnect with the rest of the cast if nothing else.

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"I would love to reboot only to be able to hang out with this group of people, the talent," Wen, 57, said. "As you get older, the appreciation level and the awareness is so much greater. Just such great fortune. I would love to have been, even now… just even this, surrounded by these people."

That was a sentiment that Clooney could get behind — the actor said he was "excited" when asked to join the reunion call.

"I'm excited to see this gang," he said, going on to address his former cast mates. "These are people that I really love, you know, and that — we grew up together, really grew up together, in many ways, and it's fun to see you guys."