Somebody out there is overdue for a smack upside the head.

"Friends" star "Watch What Happens Live" -- she's part of the voice cast for "The Boss Baby" and co-stars in "Table 19," which are both out this month -- and she answered a fan question.

The fan asked Kudrow, without naming names, what was the worst behavior she ever saw from a guest star on "Friends"?

Here's her answer:

"The worst behavior, off the top of my head? 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 —' Can I say it? 'Now you're f*ckable'. That's bad behavior, I'd say."

Host Andy Cohen said "Wow," and the audience ooooohed, although some laughed. Fellow guest Jennifer Beals asked Kudrow if she retaliated against the guest star.

"I told Matt LeBlanc. He's like a big brother."

Let's hope Joey had some choice words for this totally un-f*ckable guest star. Could they BE more obnoxious?

[via: Entertainment Weekly]

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