Initial sessions for "Helter Skelter" were so intense that they ultimately included the longest song the Beatles ever recorded: a 27-minute version of the track that later appeared on their self-titled double album in abbreviated form.

The same sessions, held on July 18, 1968, also produced takes that were more than 10 and 12 minutes long. These lengthy jams ended up creating no small amount of technical issues with the equipment of the day, but this too proved to be inspirational as the song's writer, Paul McCartney, moved toward a final idea of what "Helter Skelter" would be.

Put simply, they were running out of tape – and nobody wanted to interrupt the band's collective train of thought.

"They recorded the long versions of 'Helter Skelter' with live tape echo," engineer Brian Gibson told Mark Lewisohn in The Beatles Recording Sessions. "Echo would normally be added at remix stage, otherwise it can't be altered, but this time they wanted it live." As the tape grew shorter, the technical crew had to make a decision.

"The Beatles were jamming away, completely oblivious to the world and we didn't know what to do, because they all had fold-back in their headphones so that they could hear the echo. We knew that if we stopped it, they would notice," Gibson said. "In the end, we decided that the best thing to do was stop the tape echo machine and rewind it. So, at one point the echo suddenly stopped and you could hear 'bllllrrrrippppp' as it was spooled back. This prompted Paul to put in some kind of clever vocal improvisation based around the chattering sound!"

McCartney had made a very rough, acoustic-based pass at the song earlier in June, while in a room with his girlfriend, John Lennon and Yoko Ono during a promo shoot at EMI's Studio Two. He'd been inspired to try the noisiest thing the Beatles had ever done by a description of the Who's recently released song “I Can See For Miles.”

"I was in Scotland and I read in Melody Maker that Pete Townshend had said, 'We've just made the raunchiest, loudest, most ridiculous rock 'n' roll record you've ever heard,'" McCartney recalled in Anthology. "That got me going, just hearing him talk about it. So, I said to the guys, 'I think we should do a song like that; something really wild.' And I wrote 'Helter Skelter.'"

By the time these elephantine demos were being made, the group had already spent seven hours working on “Cry Baby Cry,” one of Lennon’s songs, before returning at 10:30PM to try “Helter Skelter.” The Beatles – with McCartney on vocals and lead guitar, Lennon on bass, George Harrison on rhythm guitar and Ringo Starr on drums – were still banging away at 3:30AM.

Listen to the 'Anthology' Version of the Beatles' 'Helter Skelter'

Ultimately, they put these recordings aside. The finished version of "Helter Skelter" emerged from sessions held on Sept. 9, 1968, building off the 21st take. Overdubs were completed the following day. But the original rehearsal tapes were not forgotten. The 12-minute version was later included on 1996's Anthology 3, though it was cut down to 4:37 – much to Lewisohn's consternation.

"I made it clear to George Martin when we doing Anthology 3, that the fans are desperate to hear [the earlier versions] and I urged him to listen to it, because I don't think initially he was going to do so," Lewisohn said. "He listened to it, and he said, 'Well, why is this important?' I said forget the quality of the sound, or forget the fact that it's not quite in tune or whatever – what a producer would normally be looking for. Just respect the fact, please, that it is hailed as the most important outtake of them all, and the fans will go crazy if you don't include this on the Anthology."

In the end, Lewisohn continues to argue for the release of the full 27-minute take. "They said, 'This is all people will stand, they won't stand the whole thing,'" he added. "And I said, 'Well, I think a lot of them will, actually.'"

By the '90s, "Helter Skelter" – which McCartney named after an amusement-park ride – had witnessed plenty of highs and lows. The White Album was a multi-platinum smash. The song itself was later issued as a double-sided single that reached the Billboard Top 10 in 1976. But "Helter Skelter" also became closely associated with the grisly murders committed by Charles Manson's crime family.

“You could have thought of it as a rather cute title, but it's since taken on all sorts of ominous overtones because Manson picked it up as an anthem," McCartney told Barry Miles in Many Years From Now. Then again, he noted, "quite a few punk bands have done it, because it is a raunchy rocker."

Mission accomplished.

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