George Clooney is the King of Pranking.

The level of glee he feels after successfully pulling a fast one on his buddies his palpable. His fans love hearing about the mischief this A-list talent has gotten into. There's even a timeline of all of his most famous pranks, including the kitty littler prank he pulled on Richard Kind.

There are countless celebrities who have been pranked by the modern-day Cary Grant. Even Leslie Jordan claims to have been pranked by the Michael Clayton star. Of course, George's most famous pranks have been targetted at his Ocean's Eleven castmates, like Brad Pitt and Matt Damon.

But what he did to Richard Kind and his cat is just so above and beyond hilarious awful.

Some Important Context

George Clooney is now one of the most accomplished and sought-after actors in Hollywood. He's also happily married to the brilliant Amal living the high-life with her and his new family in exotic and glorious locations. But before his star-making turn in 1994 television series ER, he was down on his luck.

Specifically, he was a struggling actor who just got divorced from Talia Balsam. Due to his circumstances, he was forced to move into a three-story walk-up in New York with his buddy, comedian Richard Kind.

Related: 20 Most Beautiful Women George Clooney Was Linked To (Before Amal Alamuddin)

Curb Your Enthusiasm fans know Richard Kind as Cousin Andy. But he famously starred in the sit-com, Spin City, voiced the character of Bingbong in Inside Out, and lent some comedy to the Coen Brother's cult-classic, A Serious Man. But he too wasn't the most successful in 1993. Still, he had enough money to let George come live with him for a few months. According to Vulture, George later repaid Richard for his generosity once he made it big...

But not before pranking him a few times...

George LOVED Pranking Richard

During Richard's interview with Kevin Pollack, he described the level of energy that George put into his pranks. George would also be relentless in his pursuit of pranking Richard, who admitted to being an easy target. After all, Richard is an already neurotic New Yorker who'd never see these pranks coming.

For instance, while driving, George would get Richard to look out the window right as George drove over a water-filled pothole... Richard would, of course, get soaked.

Then there was the time that George convinced Richard that he was going to art classes just so he could guilt Richard into putting up an absolutely hideous painting that he said he painted... George actually found it in the trash and wanted to pull a fast one on the poor Serious Man star.

Related: Carole Baskin Just Got Seriously Pranked!

Seriously, poor Richard.

But Richard's beloved cat was the center of George's meanest prank.

The Empty Litter Box

While George Clooney had really only done The Facts of Life and not any of his most brilliant films, he was a creative genius even in 1993.

He actually convinced Richard Kind that his cat hadn't gone to the bathroom in weeks. And then paid this off with the mother-of-all animal-related pranks.

Richard, a self-appointed "typical New York Jewish comedian", had a big fluffy cat named Fluffernutter. And he loved this cat. So much so that he noticed that the cat's litter-box, which was kept in the bathroom, was empty for days on end.

This pushed Richard to take the cat to the vet to get some dietary pills. Richard followed the vet's guide and fed these pills to his poor cat in hopes it would get him to relieve himself.

But days later... there was still nothing in the litter box...

Little did Richard know, George was secretly emptying the box for weeks.

The cat never had any bowel issues, to begin with. Everything was fine.

Although, we're sure the pills that Fluffernutter was put on didn't help matters. In fact, Richard wanted to complain to the vet that the pills weren't working.

One day, Richard came into the bathroom to find an "absolutely enormous s**t" in the litter-box.

This caused the basally voiced comedian to shout out, "Oh my God! Kitty!".

Turns out, Geroge had actually squatted over the litter-box and dropped one of his own gems...

Yep, you read that right... George s**t in the litter-box.

Related: 15 Best On-Set Pranks Actors Pulled On Each Other

Richard And George Remain Friends

Nowadays, George Clooney is up to a lot of different things, but he's still pranking left, right, and center. Although we're sure Richard Kind isn't his main target. After all, hasn't the man suffered enough?

A prank like this could easily break-up a friendship, but through it all, Richard and George have remained close. Richard was even one of the few celebrities invited to his famous wedding to Amal.

Of course, it didn't hurt that Richard Kind had (and still has) a comedian's sense of humor. Meaning that he can actually take a joke. Wouldn't it be nice if we all could do that?

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