Like any good story, the documentary about the making of the Beatles’ latest album — neither of which existed yet — needed a climax.

It was Jan. 30, 1969, and the world-renowned rock band decided to stage a performance on the roof of its Apple Corps building in London for family, friends and film cameras. The 42-minute show became the grand finale of the band’s documentary, “Let It Be.”

It was also the last public performance that the most commercially successful band in history would ever give. As police shut down the show for causing a ruckus, John Lennon declared: “I’d like to say thank you on behalf of the group and ourselves, and I hope we passed the audition.”

“It wasn’t an audition,” said Beatles historian Mark Lewisohn. “But they always had the perfect lines.”

The rooftop show and the associated “Let It Be” album are at the heart of Peter Jackson’s three-part documentary series “Get Back,” which has earned a strong critical reception and catapulted the album into the UK Top 40, more than a half century after its release.

But the band’s rooftop performance didn’t capture much attention at the time. That evening’s BBC News bulletin didn’t mention it, Lewisohn said, and the next day’s newspapers ran stories about it on the inside. People who gathered on the street during the show couldn’t see the band and weren’t even sure it was the Beatles.

But to those who watched from atop the office on Savile Row and from nearby rooftops, the lunchtime performance was a chance to see a band that was just as sharp and strong as ever. The Beatles were candid with the cameras because they knew the film’s editing was within their control, Lewisohn said. The album and documentary project, initially called “Get Back,” were meant to showcase the band’s music without studio artifice.

Before they decided to play on the roof, the Beatles argued over where to perform, according to Philip Norman’s book, “Shout!: The Beatles in Their Generation.” Los Angeles? A Tunisian amphitheater? On an ocean liner? In the midst of the argument, Lennon muttered, “I’m warming to the idea of having it in an asylum.”

The asylum proved unnecessary. Keyboardist Billy Preston, who performed with the Beatles on the rooftop, said the location was Lennon’s idea. They announced it the night before the performance and worked into the night to prepare.

“They were worrying about where they could play and how to fit everyone into a concert hall,” Preston said in Andy Babiuk’s book “Beatles Gear: All the Fab Four’s Instruments from Stage to Studio.” “They didn’t want to tour, they wanted to do one concert where everyone could come.”

“Everyone” turned out to be about 30 people: Lennon’s wife, Yoko Ono; Ringo Starr’s wife, Maureen Starkey Tigrett; an American executive from Capitol Records; people who worked in the Apple Corps building; people visiting the building; still photographers and the film crew. Lennon and Starr, both 28, wore their romantic partners’ coats during the performance to protect against the cold. George Harrison, 25, donned green trousers.

Engineer Alan Parsons told Guitar Player that another engineer recording the concert sent him to buy pantyhose to put over the microphones to minimize noise from the wind.

“I walked into this department store and said, ‘I need three pair of pantyhose. It doesn’t matter what size,’” Parsons told the website. “They thought I was either a bank robber or a cross dresser.”

The show’s setup was meant to create the feel of a live performance but with the sound quality of a studio recording. Cables running from the roof to the basement studio captured the music, and speakers were tilted downward toward pedestrians on the street. The band played “Get Back,” “Don’t Let Me Down,” “I’ve Got A Feeling,” “The One After 909” and “Dig A Pony” — some of the tracks multiple times.

Although the Beatles had not performed live in more than two years, Lewisohn said the show went off without a hitch.

“Their timing is perfect, and their harmonies are perfect, and the musicianship was perfect, and everything worked,” he said.

Behind the scenes, the band’s unity was being held together by a thread. They disagreed about their management. Harrison walked out of a rehearsal, declaring in a temporary moment of anger that he was quitting the band. The members frequently discussed breaking up.

By then, the Beatles had sold hundreds of millions of records, dominating the charts in the 1960s.

After they recorded their album “Abbey Road,” the Beatles went their separate ways in August 1969. Shortly after they publicized the split the next April, they released the album “Let It Be,” with songs they had sung on the rooftop and on other days that month. A documentary by the same name featured film from the rooftop concert and chronicled the album’s creation.

The release of both projects was forever clouded by coinciding with the announcement that the Beatles would not play together again, Lewisohn said. But on the day of the rooftop concert, no one would have been able to tell that the band’s days were numbered. Like many of their shows before it, the performance was brilliant, Lewisohn said.

“Everything was right with the Beatles,” he said. “Always.”

A version of this story was originally published on Jan. 30, 2019.

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