Billy Connolly once revealed he was diagnosed with a sleeping disorder after a particularly disturbing dream about murdering Sir Paul McCartney.
Sir Billy, 79, suffers with Parkinson's disease but was recently diagnosed with a sleep behaviour disorder as he has trouble when he drifts off.
The legendary comedian is known for his foul-mouthed jokes on stage, but also recently revealed he can't even stop swearing in his sleep.
The Big Yin went into more detail about his recent diagnosis in his memoir, Windswept And Interesting.
"I yell and swear and thrash about," he confessed, "and have done so for years."
"Recently, I was diagnosed with sleep behaviour disorder because, apparently, I have raging battles during the night.
"I rarely remember the fights, although I did once wake up in horror after dreaming I’d murdered Paul McCartney and buried him at the traffic lights in Glasgow Cross."
Despite the disturbing dream about The Beatles frontman, Billy dismissed his swearing outbursts in his sleep as just another part of life.
"Almost everybody swears," he shrugged.
"George Square in Glasgow is the place to hear swearing. That’s where you see swearing experts."
He added: “I’ve never tried to control my swearing. People have criticised me for it: ‘Oh, he swears too much,’ but I care not a jot."
Fondly referring to his obscenities as an art-form, he explained: "I like it. Swearing is very natural for me – and for most Glaswegians – and we’re very, very good at it.
“If you’re going to take up swearing, you have to learn how to do it properly, and make it sound like it’s normal conversation with a normal meaning.
“Glasgow swearing is extremely sophisticated. It’s a highly developed art.”
Billy was diagnosed with Parkinson's while undergoing surgery for early-stage prostate cancer in 2013 and retired from live comedy five years later.
Sir Billy confessed he would live in Scotland again at the 'drop of a hat' after years living stateside with his wife Pamela.
He continued: "Oh yeah, I would live there at the drop of a hat. I think it's a great place to live.
"I've got the whole family to think about. They've all got jobs and careers.
"I don't really think much about where I'm going to live. I live where I am.
"You may not believe this but Pamela went and bought a house in Quay West and didn't tell me.
"She sold the New York house, so I had nowhere to live. I had to come here.
"She just does that. It makes life very interesting.
"Glasgow is very much my home."
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