Courteney Cox on the 'Unbelievable,' 'Emotional' Friends Reunion: 'A Lot of Special Surprises'

For Courteney Cox, taping the upcoming Friends reunion was nothing short of an "unbelievable" experience.

"It was so emotional," the actress, who played Monica Geller on the hit NBC comedy from 1994 to 2004, said while appearing on The Ellen DeGeneres Show Thursday.

She continued of the special, taped last month, "It's an unscripted reunion, but we got to be on Stage 24 for the first time, all of us, in like … 17 years."

Cox, 56, admitted that she has "the worst memory," but during her time on Stage 24 with the rest of the core cast — Jennifer Aniston, Lisa Kudrow, Matthew Perry, Matt LeBlanc and David Schwimmer — "everything came up that I [had forgotten] about."

"But it was great. It was really fun," she continued. "We had a lot of special surprises, and it was fantastic. It really was."

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David Bjerke/NBCU Photo Bank Friends cast

Michael Rozman/Warner Bros. Courteney Cox on The Ellen DeGeneres Show

RELATED: Courteney Cox Shows How She Channels Her Friends Character in Her Daily Life: "Tell Me You're a Monica"

Cox also dished on the iconic fountain scene in the show's opening credits, saying it "definitely wasn't" her idea but that "somebody thought that would just be really fun."

"We were in that fountain for a long time," she said. "And let me tell you what happens: It's not fun to be dancing in a fountain for hours and hours."

"I remember Matthew Perry saying at one point ... 'Can't remember a time that I wasn't in this fountain,' " Cox recalled. "Literally, we were just like, 'Oh my God, how much longer am I gonna pretend I love dancing in the water?' It was fun, but not really."

"I should've directed that; you would've been out real fast," Ellen DeGeneres joked.

NBC/NBCU Photo Bank via Getty Friends cast

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Friends originally aired for 10 seasons on NBC from 1994 to 2004. The reunion special was first announced in February 2020 by HBO Max and was scheduled to premiere that May, but was delayed indefinitely due to the COVID-19 pandemic.

After confirming that the reunion had been pushed back, former WarnerMedia Entertainment and Direct-to-Consumer chairman Bob Greenblatt said they still planned on taping the special in front of a live studio audience on the soundstage in Burbank, California.

While Schwimmer, 54, couldn't say much about the reunion during a recent appearance on The Graham Norton Show, the actor, who played Monica's brother Ross Geller on the series, confirmed that he and his costars would be appearing as themselves, and not in character.

"There's nothing scripted, we're not in character," he explained. "We are all ourselves, although there is one section of it that I don't want to give away, but we all read something."