CHICAGO (NewsNation) — The Beatles are set to release their first song in decades that has been in the making for more than 40 years.

With two of the quartet’s members now dead, artificial intelligence has played a large role in producing what is promised to be the last “new” Beatles song.

John Lennon, Paul McCartney, George Harrison and Ringo Starr are all reunited, even in the afterlife, on this track. The song is scheduled to be released on Thursday at 9 a.m. ET.

The new song will welcome a new generation of rock ‘n’ roll to a band that changed the music industry forever.

“To hear John’s voice, that’s a thing that we should cherish,” Harrison said, “and I’m sure he’d really love the opportunity to be with us again.”

The track, called “Now And Then,” will be a part of a single paired with “Love Me Do,” the very first Beatles single that came out in 1962 in England. Lennon first recorded a demo of the song at his home in New York City back in the late 1970s — the same home where he was killed a few years later.

“When we lost John, that’s when we knew it was really over,” McCartney said.

John Records Landecker, a Chicago radio legend, said that the Beatles were able to take a very raw tape that Lennon recorded onto a cassette and use modern technology to isolate his voice.

“Once you do that, you can add anything you want to it,” Landecker said.

Lennon had recorded the track after the band broke up in 1970, and the song was never released with the full group performing together.

But now, with the help of AI, director Peter Jackson was able to remove the “muddled recordings” of Lennon’s voice from decades ago. The much clearer vocals allowed McCartney and Starr to complete the track last year.

“It’s an astounding thing that after all these years, there is going to be one final Beatles single that no one has ever seen or heard before. And that’s, that’s monumental on a whole bunch of different levels,” Landecker said.

The survivors packed plenty into it. The new single contains guitar that Harrison had recorded nearly three decades ago, a new drum part by Starr, with McCartney’s bass, piano and a slide guitar solo he added as a tribute to Harrison, who died in 2001. McCartney and Starr sang backup.

McCartney also added a string arrangement written with the help of Giles Martin, son of the late Beatles producer George Martin.

As if that wasn’t enough, they weaved in backing vocals from the original Beatles recordings of “Here, There and Everywhere,” “Eleanor Rigby” and “Because.”

“There it was, John’s voice, crystal clear,” McCartney said in the announcement. “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 quite an exciting thing.”

Harrison’s widow, Olivia, said he felt in the 1990s that the technical problems made it impossible to release a song that met the band’s standards. With the improvements, “he would have wholeheartedly” joined Paul and Ringo in completing the song now if he were still alive, she said.

A music video for the song is set to be released on Friday with previously unseen footage of the Beatles.

“It will blow your mind, I mean, truly,” Landecker said.

The song will premiere on the Beatles’ YouTube page.

Later in the month, expanded versions of the Beatles’ compilations “1962-1966” and “1967-1970” will be released. “Now And Then,” despite coming much later than 1970, will be added to the latter collection.

The surviving Beatles have skillfully released new projects, like remixes of their old albums that include studio outtakes and Jackson’s “Get Back” film, usually timed to appeal to nostalgic fans around the holiday season.

This year, it’s the grand finale of new music.

“This is the last track, ever, that you’ll get the four Beatles on the track. John, Paul, George, and Ringo,” Starr said in a recent interview with The Associated Press.

The Associated Press contributed to this report.