George Clooney has opened up about having Bell's Palsy when he was a teenager.
The actor appeared on Jimmy Kimmel Live! on Thursday where he explained why he looked different in some photos.
The host was showing photos of George in his younger years while he appeared alongside Snoop Dogg on the show.
However, George soon pointed out that he had Bell's Palsy during that time of his life.
On the 20th anniversary episode of the talk show, which was a recreation of the show's first episode from 2003, Jimmy brought up school photos of the celebs.
Woman falls to death from 60ft-high flat window putting up Christmas decorationsAs Jimmy showed one of the school pics, George said: "Now wait, I want to point out something because you're going to laugh, gonna make a joke. I have Bell's palsy there and half of my face is paralysed."
"Look at this, watch this," the actor explained, as he reached across the desk to cover half his face in the photo with his hand to show his smile was slanted on one side.
He added: "If you go like this, on the other side, it's a completely different face. So now make your joke. Come on, funnyman. Come on, let me give you my sad face."
However Jimmy admitted that he wasn't going to make a joke and replied: "You know what? I didn't have a joke, George, and you really brought everybody down."
According to Mayo Clinic, Bell's Palsy is a condition that causes sudden weakness in the muscles on one side of the face.
In most cases, the weakness is temporary and significantly improves over weeks.
The weakness makes half of the face appear to droop with smiles being one-sided, and the eye on the affected side resists closing.
Jimmy went on to show some throwback photos of George Clooney as well, with George commenting on his haircut at the time.
Talking about his bowl cut, George said: "I want to point out that my mother cut my hair."
The segment ended with a photo from Clooney's senior year where he is more recognisable, with Jimmy saying what a "progression" he had.
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