The final Beatles song - Now and Then.

A new Beatles song called "Now And Then" is being released 45 years after John Lennon started writing it. The full Fab Four are featured thanks to artificial intelligence technology.

What's going on here?

The "last Beatles song" debuts Thursday on streaming platforms after AI cleaned up and isolated Lennon's original vocals from a 1978 demo tape.

What does this mean?

Lennon recorded himself singing and playing piano for the song in New York two years before he died. The other Beatles tried completing the track in 1995 but struggled with the poor sound quality of Lennon's tape.

Director Peter Jackson revived the project recently while making the Beatles documentary "Get Back." He used AI to remove background noise and improve Lennon's vocal audio so it could be properly mixed with new instrumentation. Paul McCartney said this technology let them get John's voice "pure" and finish the song like normal.

George Harrison, who died in 2001, will be heard in some guitar sections from the 1995 sessions.

Why should I care?

This is an exciting chance to hear the Fab Four together in a "new" song decades after their breakup and deaths. The use of AI opens possibilities for reviving more old recordings or even creating new music posthumously.

But it also poses ethical questions around consent and manipulating the art of dead artists. As a Beatles fan, you may be thrilled to get one last song but conflicted on how it was created. This release foreshadows issues that will arise as AI generates new content mimicking real people, including the dead.