Joyous, tedious, euphoric and fab, “The Beatles: Get Back” feels like a documentary made yesterday rather than 52 years ago, an epic reimagining-cum-excavation by director Peter Jackson of the “Let It Be” studio sessions, the famous rooftop concert, and the breakup of the band because of Yoko Ono—or Paul McCartney’s ego, or manager Allen Klein’s chicanery, or George Harrison’s frustrations. None of which is true from what we see, which is often chaotic but more frequently bliss.

Director Michael Lindsay-Hogg, whose protean...

Joyous, tedious, euphoric and fab, “The Beatles: Get Back” feels like a documentary made yesterday rather than 52 years ago, an epic reimagining-cum-excavation by director Peter Jackson of the “Let It Be” studio sessions, the famous rooftop concert, and the breakup of the band because of Yoko Ono —or Paul McCartney’s ego, or manager Allen Klein’s chicanery, or George Harrison’s frustrations. None of which is true from what we see, which is often chaotic but more frequently bliss.

The Beatles: Get Back

Begins Thursday, Disney+

Director Michael Lindsay-Hogg, whose protean rock videos included “The Rolling Stones Rock and Roll Circus,” which had featured John Lennon, was enlisted by the Beatles to memorialize their self-imposed makeover: They had ceased touring or any live performance in 1966, and the subsequent records, especially 1968’s so-called “White Album,” were marked by a drifting apart. Technology, including advances in multitrack recording, meant they didn’t even have to play together. The idea behind “Let It Be” was a return to a more basic music, stuff they could play together, live, which would lead to an album, a TV special directed by Mr. Lindsay-Hogg and a live performance—perhaps in the picturesque Sabratha Amphitheater in Libya (a real idea that keeps getting brought up, and shot down).

They are given about three weeks at Twickenham Film Studios by Denis O’Dell, producer of “The Magic Christian,” the film in which Ringo Starr would appear opposite Peter Sellers. Both the facility and Mr. Starr have to be returned to O’Dell by month’s end, when shooting is to start on his film. The Beatles have only a vague idea of what they’re doing—there’s no concept for the TV show, no plausible venue for the performance, and the songs have yet to be written. The atmosphere isn’t quite fraught, but the schedule is crazy.

As plans collapse, the TV special is abandoned and the grandiose concert becomes the free lunchtime gig in London. Mr. Lindsay-Hogg is heard to say he doesn’t know what his film—they’ve decided to make a film—is going to be about. He can’t see it, but Mr. Jackson—with more than a half-century of hindsight, 60 hours of film and 150 of audio to draw on—can, very clearly. It’s not the story of “Let It Be.” It’s the most Beatle-maniacal epic imaginable, partly because it renders so naked the band’s creative process, and presents their personalities so deeply: Mr. McCartney is the dominant force, his patronizing attitude toward Harrison prompting the latter to quit the band for a few days midfilm; Mr. McCartney then pulls himself back, to admirable effect. Lennon, with Ms. Ono ever at his side or his feet, is not the abrasive or sarcastic character he presented in, say, “A Hard Day’s Night” but is sweet, funny, deferential to his longtime/no-longer songwriting partner (though everyone collaborates on everything). Mr. Starr is everyone’s friend. (The series’ three episodes—at 157, 173 and 138 minutes, respectively—roll out Thursday, Friday and Saturday.)

The portrait we get, of the most influential musical group of the 20th century, is not candid—they always know they’re being filmed, act up accordingly and often avoid the hard work of their own songs by defaulting to rockabilly and blues-based numbers from their youth. (Their early days playing Hamburg, West Germany, are evoked numerous times, as is their manager Brian Epstein, whose death in late 1967 left them with no “discipline,” as one Beatle says.) What a viewer might have trouble keeping in mind is that when the Beatles talk about the old days, they’re talking about only five or six years earlier.

Some of the more revealing moments are attained by eavesdropping. Mr. Jackson has said in interviews that by using advanced artificial intelligence, he and his technicians were able to erase the noise by which the Beatles masked their more intimate conversations—one can see in the background, on numerous instances, Harrison strumming his guitar, intentionally thwarting Mr. Lindsay-Hogg’s boom mics, which were intended to pick up everything. One of the more touching sequences in the documentary, in fact, involves a hidden mic in a flower pot picking up a private conversation between Lennon and Mr. McCartney, who discuss Harrison’s return to the band and the existing problems therein. (“The Beatles have been in the doldrums for at least a year,” Mr. Starr has already noted, apparently referring to the Epstein loss.) Harrison will return, Mr. McCartney predicts, “and probably, when we’re all very old, we’ll all agree with each other and we’ll all sing together.” It’s heartbreaking. (Lennon was assassinated in 1980; Harrison died of cancer in 2001.)

Using the same technology he employed to enliven his World War I documentary epic “They Shall Not Grow Old,” Mr. Jackson makes “Get Back” look like it took place in 2021 (it was originally shot on 16mm film; one cannot tell). One of the misconceptions about “Let It Be” (the original title of the 1969 project was “Get Back”) is that it marked the end of the Beatles. It was a useful storyline, but it’s not true, as you see in Mr. Jackson’s version. “Let It Be” was released after “Abbey Road,” but “Abbey Road” was really the final Beatles album—its songs in only nascent form during the January 1969 sessions in the film—and included what would have made the perfect last lyric to the Beatles’ career: “And in the end / The love you take / Is equal to the love you make.” With “Get Back,” Mr. Jackson doesn’t make love to the Beatles, exactly, but he gives you all you need.