A friendship between Deep Purple and George Harrison turned into a raucous jam on Dec. 13, 1984, when the former Beatles star joined them onstage in Sydney, Australia.

Harrison was pals and later neighbors with both Deep Purple drummer Ian Paice and the late keyboardist Jon Lord, and that informality was on display from the first in this once-in-a-lifetime musical collaboration. A vacationing Harrison was introduced to Australian fans as "Arnold Grove from Liverpool" – a reference to George's childhood address. He and Deep Purple proceeded to make an extended run through the Little Richard hit "Lucille."

"We were very close, I adored him. He was one of the most delightful of men," Lord once told Rick Wakeman in a rangy talk. "I thought he was an astonishingly good musician. I thought he had a way of looking at harmony that was quite unusual. He's often overshadowed – and people have said that before. It's not an original thought. But he was often overshadowed by [John] Lennon and [Paul] McCartney because they were so prolific."

In addition to video (which you can watch below), there's also a backstage photo commemorating the moment featuring Lord, Harrison and a soaking-wet (and almost naked) Ian Gillan, who apparently had just taken a shower.

Watch George Harrison Perform With Deep Purple

Back then, Lord had recently appeared on Harrison's 1982 album Gone Troppo, but their relationship traced back to the '60s. Lord has said they first met at the Beatles' Apple boutique in London, telling Wakeman that a winking Harrison "stood in front of me and said rather quizzically, 'Oh, you look like me!' I looked at him and, because it was George Harrison, I said, 'Well, I'm sorry!' We became friends about a year later, mainly because of him living nearby." Around that time, Lord and Deep Purple were heard doing a cover of the Beatles' “Help!”

Lord and Harrison subsequently contributed to 1971's The Worst of Ashton, Gardner + Dyke; a loose local amalgam called Pishill Artists that played a Henley-on-Thames area pub; and a soundtrack for the 1985 British comedy Water, starring Michael Caine. Lord also appeared on Harrison's posthumous 2002 album Brainwashed.

Paice, meanwhile, was a fellow member of Pishill Artists who later worked with Harrison on three bonus songs for Best of Dark Horse 1976-1989 – including "Cheer Down," which was used on the soundtrack for 1989's Lethal Weapon 2. Harrison and Paice appeared on "Anna Julia," from Traffic star Jim Capaldi's 2001 album Living on the Outside too.

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