Lisa Kudrow shared a behind-the-scenes anecdote from the days of Friends — a show that remains enduringly popular, gaining new audiences through Netflix and syndication deals like MTV's 2-hour "dinner with Friends" block — and it's got us scrolling through our mental index of every single actor who ever guest-starred on the sitcom.

Kudrow shared the story during a March 1 episode of Andy Cohen's Watch What Happens Live, after a caller asked her what the "worst behavior" she'd ever witnessed from a Friends guest star, of which there were so many.

"The worst behavior, off the top of my head?" Kudrow  "I rehearsed without makeup most of the week, and then on show night, I’m in hair and makeup, and I was told, 'Oh wow, now you’re f—able.' That’s bad behavior, I’d say."

Actress Jennifer Beals, another guest on the WWHL episode, asked if she took any action in response, and Kudrow said "I told Matt LeBlanc," who played Joey on the 10-season show, because "he's like a big brother."

It's difficult to wildly speculate on who could've possibly made the rude offhanded remark, given how many people guest-starred on the show. Even restricting the guesses to men, here's just a small handful — and those are just the famous ones:

George Clooney and Noah Wyle
Tom Selleck
Brad Pitt
Ben Stiller
Charlie Sheen (hmmm)
Billy Crystal
Hugh Laurie
Gary Oldham
Elliott Gould
Tate Donovan
Sean Penn
Bruce Willis
Jeff Goldblum
Alec Baldwin
Dermot Mulroney
John Stamos
Jean-Claude Van Damme

Any guesses?

Kudrow, who joined Taylor Swift onstage during the 1989 World Tour for a live rendition of Phoebe Buffay classic "Smelly Cat" in 2015, answered another caller's question about whether the gig offered "squad status" or "any perks."

"Oh, perks? Yeah, 'cause I got a Christmas gift," Kudrow said.

"Ooh, what'd you get?" Andy Cohen asked.

"Oh, well, there's a blanket, like from her show. Tour." Kudrow said, making Phoebe-esque gestures that may indicate autographs are involved. "And other things, I can't remember. A picture. I don't know! It was a good...I can't remember," she concludes, with a hilarious expression that reminds us why she's a comedy icon.

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