We all know and love 'SNL' for the show's most iconic and hilarious sketches. However, behind the scenes, things aren't always smooth, especially in the writers' room.

Certain celebs aren't the easiest to deal with, heck Justin Bieber was labeled as a bully behind the scenes.

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We've heard lots of other stories from the cast along the way, including Tina Fey being very critical about certain celebs. We'll take a look at certain reality stars she ripped in the past, including a certain judge from 'American Idol'.

Although 'SNL' is known for its hilarious skits, things aren't always that smooth behind the scenes. In truth, controversy has taken place both backstage and even on the stage.

In truth, some of the celeb guests aren't always well-received by the cast. We have more than a few examples, including Kanye going off-script, making a political rant, and asking the 'SNL' cast to join him on stage... 'SNL' vet Kenan Thompson stated that the room went silent while this was taking place. Heck, Pete Davidson literally exited the stage...

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That's just the start, others like Justin Bieber were viewed as tired and completely out of it during their time on the show. While Steven Seagal is typically called the worst host ever. Not only was he unfunny on-screen but according to the likes of David Spade, he really wasn't open to much in terms of what the writers wanted to do with him.

During her time on the show, Tins Fey was always very open with her thoughts and opinions on certain guests. In truth, she has roasted more than one guest in the past.

Tina Fey Roasted Paris Hilton And Adrien Brody For Their Time On 'SNL' In The Past

Getting an Oscar-award winner should be a big deal but according to Tina Fey, that was not the case and instead, very much the opposite. Fey called Adrien Brody "cocky and unfunny" during his time on the sketch comedy show.

"Adrien Brody was super cocky and came and sat in the writers' meetings and was pitching loads of terribly unfunny ideas."

Brody's skit turned out to be one of the very worst ever when the actor tried to mimic a Jamaican man... which would come off as distasteful.

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In truth, Brody got off easy compared to the words Fey had for Paris Hilton alongside Howard Stern, "She was awful. People never come in and say "I'm not doing that." So, this guy Jim Downey wrote a really really funny sketch, it was supposed to be Lorne Michaels just finding out that she had a sex tape and telling her she couldn't host the show because SNL has standards... So she was like "I'm not doing it!"

The cast would also run a bet behind the scenes, wondering if Hilton would ask anyone a personal question, "The cast had a bet if she would ask anyone on the cast anything about themselves, you know like how are you? where are you from? anything. I think Seth Meyers won because, at one point, she asked him if Maya Rudolf was Italian."

Turns out, that wasn't the last of Fey's rant, as she also had some choice words for yet another guest star.

Tina Fey Ripped Paula Abdul's Short-Lived Cameo On The Show

While she was pregnant, Tina Fey recalls Paula Abdul's cameo, which in her words, was not a good one. So much so that Adbul refused to play herself in a particular skit.

“It was an ‘American Idol’ sketch, and she wanted to change parts. So Amy Poehler had to play her.”

“I was pregnant at the time and probably a little moody, but I remember thinking, ‘She’s a disaster! I gotta prop this lady up and get her on TV.’ ”

Following Fey's harsh words alongside Playboy, the two would meet shortly after on a flight. Fey confirmed, Abdul was not happy to see her, making it clear she didn't have a good time on 'SNL' either.

“A year later I saw her on a flight,” Fey tells the latest edition of Playboy. “We both looked at each other like, ‘Do I know that girl?’ And then we both had the same moment of recognition, and she was like ‘uuuggh.’ I saw it register on her face that she had had a terrible time with us.”

Without a doubt, the two won't be doing any type of work together in the near future.

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