Revealed: Paul McCartney's Secret Agony Over The Beatles' Break-Up — And Why It All Goes Back to John Lennon

Paul McCartney has opened up about the painful collapse of The Beatles, revealing the emotional toll of the band's split and his lingering sense the blame placed on him masked a deeper truth – that John Lennon's decision to leave the group triggered the end of the most famous band in music history.

OK! can reveal McCartney, 83, reflected on the chaotic aftermath of the band's breakup while discussing Man on the Run, a new documentary exploring his life after The Beatles.

The film, directed by Morgan Neville, traces McCartney's journey through the early 1970s as he rebuilt his career with the band Wings following the group's implosion in 1970.

The period was marked by lawsuits, fractured friendships and bitter disputes over management after Lennon, George Harrison and Ringo Starr appointed New York accountant Allen Klein to run the band's business affairs – a move McCartney fiercely opposed.

He said: "Every afternoon, I had to go into the Apple office to face the latest horrible development. It was turgid, honestly a bad, bad time."

The dispute led McCartney to file a lawsuit against his former bandmates in December 1970 in a bid to dissolve the partnership that legally bound the band together. The legal fight unfolded alongside the personal fallout of losing the group that had dominated popular music throughout the 1960s.

At one point in the film, McCartney addresses the lingering perception that he was responsible for breaking up the band.

McCartney said: "John broke up the Beatles, but I got the rap… that's a bit of a weight to bear."

The emotional upheaval pushed McCartney and his wife, Linda, to retreat from London to a remote farmhouse in rural Scotland, where they attempted to rebuild their lives away from the intense scrutiny that followed the band's collapse.

Linda, who died in 1998 at age 56, became central to McCartney's attempt to start again creatively and personally.

One evening during that period, McCartney recalled watching Johnny Cash performing on television with a group of country musicians.

The moment sparked an idea that would shape his future.

McCartney said: "I thought, here's Johnny, he's doing it. So I turned to Linda and said, 'Do you want to form a band?' And she went, 'Sure.'"

That decision ultimately led to the creation of Wings, a group McCartney deliberately built from relatively unknown musicians rather than assembling an all-star lineup of established performers.

McCartney explained: "After the end of the Beatles, I was faced with certain alternatives. One was to give up music entirely and do God knows what. Another was to start a super-band with very famous people, Eric Clapton and so on. I didn't like that either, so I thought, how did the Beatles start? It was a bunch of mates who didn't know what they were doing."

Director Morgan Neville said the documentary explores how McCartney tried to rebuild a normal life after years of extraordinary global fame.

Neville said the story begins with the breakup of The Beatles and ends with Lennon's death in 1980 – two moments that reshaped McCartney's life.

Neville said: "The film begins on the day the Beatles break up and it ends on the day John Lennon dies."

He added: "Those were the seismic events that changed Paul's life."

The documentary also reveals difficult moments during McCartney's early post-Beatles years, including a period of heavy drinking as he struggled to adjust to life outside the band that had defined his career.

Neville said the singer's retreat to Scotland helped him find stability away from the legal battles and media criticism that surrounded the breakup.

Neville said: "Scotland became his fortress of solitude."

Despite criticism and uncertainty surrounding his early solo work, McCartney eventually regained confidence with Wings, particularly after the success of the 1973 album Band on the Run.

McCartney said: "The success of Band on the Run gave us confidence, especially Linda."

He added: "Instead of being made fun of because of her lack of expertise, she was getting respected."