After an hour of this lengthy three-part documentary about The Beatles, I was wondering if it was going to be nothing more than an extended jam session – gripping stuff for diehard fans, but a long haul for the rest of us. When Peter Jackson got his hands on this never-before-seen footage, he must have realised he could make something longer than The Lord of the Rings, without the wardrobe department or the CGI.

There are many occasions over the course of almost eight hours when the word “interminable” springs to mind. We watch John, Paul, George and Ringo fooling around – first in a cavernous film shed at Twickenham Studios, then in the basement of Apple headquarters in Savile Row. They go through endless renditions of their own songs and, by way of limbering up, an encyclopaedic collection of rock ‘n’ roll classics.