More than 50 years after their breakup, The Beatles released a “new” song. Called “Now and Then,” the song was initially written and partially recorded by John Lennon in the 1970s. The song, full of piano and strings and already a YouTube sensation, was made possible thanks to artificial intelligence — triggering questions about the future of music with the disruption of AI.

The story of “Now and Then” starts over 50 years ago, when John Lennon recorded a demo with vocals and piano at his home in New York. In 1994, his wife, Yoko Ono, gave the recording to Paul McCartney, George Harrison and Ringo Starr. At the same time, the three of them recorded new parts and completed a rough mix for “Now and Then” with producer Jeff Lynne.

However, the song was shelved. Technological limitations prevented John’s vocals and piano from being separated to achieve the clear mix needed to finish the song. Instead, the three remaining members of the band worked on other recordings left by Lennon, “Free as a Bird” and “Real Love” — completed and turned into songs in the 1990s.

Cut to 2021. The Beatles released the Get Back documentary series, which surprised viewers with the film and audio restoration done by director Peter Jackson. The film is largely made from footage recorded while the band was working on Let it Be in 1969. The audio had been recorded with a single mono microphone, so it wasn’t very good.

Trying to fix it, Jackson developed a machine learning technology that could distinguish the difference between instruments and voices. The technology, called MAL, was used on “Now and Then” to separate Lennon’s vocal and piano parts. Paul and Ringo recorded the backing instruments, weaving in existing recordings of the late George.

“There it was, John’s voice, crystal clear. It’s quite emotional. And we all play on it, it’s a genuine Beatles recording. In 2023 to still be working on Beatles music, and about to release a new song the public haven’t heard, I think it’s an exciting thing,” Paul said in a press release. For Ringo, “it’s the closest” they will get to having John back in the room.

Is it the last song?

The song, already played by millions on YouTube and Spotify, raises big questions about the future of AI in music and whether this technology could be replicated for other musician’s songs. While it’s probably still too early to say, in the case of The Beatles, Peter Jackson has high hopes of making more music, describing the idea as “conceivable.”

“We can take a performance from Get Back, separate John and George, and then have Paul and Ringo add a chorus or harmonies. You might end up with a decent song but I haven’t had conversations with Paul about that,” the Lord of The Rings director told The Sunday Times in a recent interview. “It’s fanboy stuff but certainly conceivable.”

However, not everyone might be on board. Alongside the song, The Beatles released a short documentary digging into the production of “Now and Then.” In it, Paul is seen as doubtful about making other songs out of John’s demos. “Is it something we shouldn’t do?”, he said. However, he also acknowledges John would likely be OK with it.

“Every time I thought like that I thought, wait a minute, let’s say I had a chance to ask John, ‘Hey John, would you like us to finish this last song of yours?’ I’m telling you, I know the answer would have been, ‘Yeah!’” said Paul. For now, we can enjoy a brand new song by The Beatles while Paul continues on a concert tour in Brazil and Australia.