I’m amazed, and there’s no maybe about it. Paul McCartney and Wings star in this engrossing hour-long documentary (or, if you will, rockumentary) shot on analogue video in 1974 (while Band on the Run was riding high in the charts) by cameraman and VFX veteran David Litchfield, as the band worked in Abbey Road on a potential live-in-studio album featuring Wings standards, early McCartney compositions and covers. It was to be called One Hand Clapping but both album and film fell appropriately silent, release plans were stalled, though the material surfaced in the form of various bonus extras over the years.

Now the film is restored and re-released and it’s a complete joy, quite as entertaining for me as Peter Jackson’s account of the Beatles’ Let It Be. McCartney’s extraordinary, unforced gusto and the delight he takes in every creative moment, his natural extrovert musicianship and casual virtuosity are such a tonic. Perhaps it’s an absurd thing to notice, but McCartney is of course still a very young man at this stage and yet he seems to have such a complete historical grasp of pop idiom; not surprising, perhaps, as he co-invented or co-reinvented pop idiom in its entirety. He shows an almost eerie, savant awareness of popular music history.

McCartney’s Wings hits are all killer no filler, we get Live and Let Die with complete orchestra and white tailcoated conductor in the studio, and McCartney also sits at the piano and gives us his stunning lounge-singer number Suicide, composed when he was just 14 years old as a number for Tony Bennett or Frank Sinatra.

And the film comes with its own bonus material: a “backyard” al fresco mini-concert. McCartney set up with chair and acoustic guitar in a bit of garden behind the studio and Litchfield shot him as, with equal musical garrulity, he played a kind of busker set, channelling Buddy Holly and Eddie Cochran, reimagining the latter’s Twenty Flight Rock as an addictively sinuous, slow-jam masterpiece. There’s plenty for nostalgists and completists to swoon over – and some hilarious incidentals, such as drummer Geoff Britton in his karate outfit busting out some martial arts moves in a spare moment. Such a pleasure.

• Paul McCartney and Wings – One Hand Clapping is in cinemas from 26 September.