Bill Murray recounts the tail of his first meeting with George Clooney and their prank involving pushing a wheelchair into a swimming pool. According to the 63-year-old Murray, he and 52-year-old Clooney became friends instantly after meeting for the first time at the Venice Film Festival a few years ago. This friendship, in part, came from an understanding that they had a very similar sense of humour after they pushed a friend around in a wheelchair before dumping him in a swimming pool.

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Murray appeared on 'The Late Show with David Letterman', recounting the night he met Clooney. Murray explained: ''I met [Clooney] at the Venice Film Festival a few years ago and it's one of those places where people from Hollywood who are square like 364 days of the year, they will get weird in Venice. I don't know why, I don't know if it's the smell of the water or what, but all of these Hollywood kinds get crazy but not George, he's not one of them."

He continued to explain that: ''We ended up having a whole lot of fun and my son said to me, 'Why were you and George Clooney pushing someone around in a wheelchair into a swimming pool?' I was like, 'You know son, why do you believe stuff like that? You know people put that in the internet, why would you ever believe something like that?' His response was, 'Well there are pictures.' ''

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Murray's appearance coincided with the 20th anniversary episode of Letterman's 'The Late Show', after Murray was revealed to be the first ever guest on the show. For the interview, Murray dressed up as Liberace, much to Letterman's amusement. Murray is set to appear on-screen with his friend Clooney in December 2013's 'The Monuments Men', in which a group of art historians attempt to recover some famous works of art which were stolen by the Nazis before Hitler destroys them.