Paul McCartney Says He Was ‘Depressed,’ Thought He’d ‘Never Write Another Note… Ever’ After Beatles Split (Exclusive)

The Beatles were Paul McCartney’s entire life. When the group parted ways, he thought his pen had run dry for good.

The English singer-songwriter, 83, opens up about his life in the wake of the break-up of the iconic British invasion band (McCartney, John Lennon, George Harrison and Ringo Starr) in the new Prime Video documentary Paul McCartney: Man on the Run.

In the trailer for the Morgan Neville-directed doc — which PEOPLE is exclusively premiering — McCartney reflects on the depression he experienced after the Beatles’ break-up, and recounts how he climbed out of it while steering his career in a new direction with his ’70s band Wings.

“I’ve always loved the Beatles, but Wings was the band putting out records when I was young,” Neville, who directed the Oscar-winning 2013 documentary 20 Feet from Stardom, tells PEOPLE exclusively. “I remember buying them in stores and obsessing over them. Having a chance to revisit this time with Paul took me back like it took him back. In many cases, Paul hadn’t thought about those times in many years. So really it was a sense of rediscovering things together.”

In the Man on the Run trailer, McCartney says, “The Beatles had been my whole life, really. When we split up, I thought I’ll never write another note of music ever. I had fear of being a grown-up.”

“I felt very depressed, but I was very lucky because I had Linda,” the musician continues, referring to his late wife and Wings co-founder, whom he married in 1969 and who died in 1998 at age 56.

In the trailer, McCartney, who executive produced the documentary, remembers the beginning of his post-Beatles band — including the moment he asked Linda to be part of it.

“Well, we’ve got two members,” he says while recounting the fateful interaction, which can be traced back to an important moment in the longtime couple’s life together. “When did you first discover Linda could sing?” a man can be heard asking in the trailer, as McCartney replies, “On the wedding night.”

Though Wings ultimately grew a sizable fanbase and enjoyed critical acclaim with hits like “Band on the Run,” “Live and Let Die,” “Jet” and “Silly Love Songs,” the band — much like The Beatles — wasn’t always beloved. It’s another stage of McCartney’s life that he grapples with in Man on the Run, the trailer teases.

“Wings was a dud when it first come out,” he recalls.

As for how he dealt with it, he continues, “If anybody badmouthed us, I was thinking, ‘I’m going to make the best record you’ve ever heard.’… People thought we were totally crazy, but that was our way.”

“Paul always felt that the ’70’s were a tough time, since everything he did was judged against the Beatles,” Neville says. “For years, people have told Paul how important Wings has been to them. Yet, I’m not sure he truly believed there was as much love for Wings and his ’70s solo work as there was.”