Tomorrow at 2pm GMT, the final song by The Beatles will be released worldwide.
Now and Then was written and recorded as a demo by John Lennon on tape in his New York City apartment before his death in 1980.
During the 1990s, the three surviving Beatles attempted to complete it as a song by the whole band.
However, it proved particularly difficult as Lennon was hidden away on the tape recovered by Yoko Ono.
In Peter Jackson’s accompanying mini-documentary, which debuts this evening, Sir Paul McCartney said: “On John’s demo tape the piano was a little hard to hear. And in those days of course, we didn’t have the technology to do the separation.”
McCartney continued: “Every time I wanted a little bit more of John’s voice this piano came through and clouded the picture. I think we kind of ran out of steam a bit and time and it was like, “Well I don’t know, maybe we’ll leave this one.”
Unlike other rediscovered Lennon tracks Free as a Bird and Real Love, Now and Then ended up languishing in a cupboard.
Macca added: “And then in 2001 we lost George, which kind of took the wind out of our sails. It took almost a quarter of a century for us to wait until the right moment to tackle Now and Then again.”
Thanks to the modern technology that Peter Jackson and his team used in The Beatles: Get Back documentary, in which they were able to separate instruments from voices, Lennon’s vocals and his piano could be too, leading to an emotional moment during the sessions.
McCartney shared: “A few seconds later or however look it took and there it was: John’s voice, crystal clear, it was quite emotional. So in the mix we could lift John’s voice without lifting the piano which had always been one of the problems. Now we could mix it and make a proper record of it.”
Macca added his bass guitar, Sir Ringo Starr his drums, but what about the late George Harrison?
He added: “We had kept George’s guitar parts from ’95 and I thought what I’d like to do is a slide guitar solo in George’s style, it was really a tribute to George. And then we started mixing it. Wow this is it, now it’s a Beatles record.
Now and Then is released worldwide at 2pm GMT on Thursday November 2 and Peter Jackson’s music video debuts 24 hours later.