The last ever Beatles song, "Now and Then," is available for listening now.

All four members of the band can be heard on the new track, with archival recordings of John Lennon and George Harrison, plus new contributions from Paul McCartney and Ringo Starr.

You can hear the song below.

A short documentary film about the making of "Now and Then" was released earlier this week, and an accompanying music video directed by Peter Jackson will arrive on Friday.

Why 'Now and Then' Was Left Unfinished

Before his passing in 1980, Lennon recorded numerous demo tapes at his home in New York City. Several of these, including "Now and Then," were given to the remaining members of the Beatles by Lennon's widow, Yoko Ono.

Unfortunately, in the case of "Now and Then," it was deemed impossible to separate Lennon's vocal from his piano playing, rendering the tape unusable. Two other demos,  "Free as a Bird" and "Real Love," were able to be completed, but "Now and Then" was shelved for approximately the next 30 years.

Then, in 2021, Jackson's filmmaking team brought in a new kind of de-mixing technology for the Emmy-winning documentary series The Beatles: Get Back. With it, Jackson could sort out individual voices, instruments and other sounds so that the audio could be re-mixed properly.

McCartney then broached the idea of using this same technology for "Now and Then." It worked, and he and Starr went about officially finishing the song.

"There it was, John's voice, crystal clear. It's quite emotional," McCartney said in an earlier press release.

"It was the closest we'll ever come to having him back in the room, so it was very emotional for all of us," Starr added. "It was like John was there, you know. It's far out."

READ MORE: 20 Beatles Songs That John Lennon Hated

Harrison's previously recorded guitar parts and backing vocals, leftover from their first attempts at the track in the mid '90s, were also added on.

"In 2023 to still be working on Beatles music," McCartney continued, "and about to release a new song the public haven't heard, I think it's an exciting thing."

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Gallery Credit: Michael Gallucci

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